2021 GMC SIERRA 1500

ENGINE AND ENGINE COOLING:ENGINE:HARD PARTS INTERNAL/MECHANICAL

General Motors LLC (GM) is recalling certain 2021-2024 Cadillac Escalade and Escalade ESV, Chevrolet Silverado 1500, Suburban, and Tahoe, GMC Sierra 1500, Yukon, and Yukon XL vehicles equipped with a 6.2L V8 gas engine. The connecting rod and/or crankshaft engine components may have manufacturing defects that can lead to engine damage and engine failure.

Risk: Engine failure increases the risk of a crash.

POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE

General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel engines. The transmission control valve may fail and cause the rear wheels to lock-up.

Risk: Rear wheel lock-up can increase the risk of a crash.

TIRES:TEMPORARY/EMERGENCY SPARE TIRE

General Motors (GM) is recalling certain 2019-2021 GMC Sierra 1500 and Silverado 1500 vehicles equipped with certain accessory road tires and a 17" spare tire. The 17" spare tire provided with the vehicle is not compatible for use with the accessory wheels, which can cause the anti-lock brake system (ABS) to not function properly under certain conditions.

Risk: An ABS system that does not function properly can increase the risk of a crash.

TIRES

General Motors LLC (GM) is recalling certain 2020 Buick Enclave, Cadillac XT5, GMC Acadia and Chevrolet Traverse vehicles and 2020-2021 Chevrolet Silverado 1500, GMC Sierra 1500 vehicles. The vehicles may have been manufactured with Continental tires that were overcured.

Risk: Overcured tires may experience a carcass break in the sidewall resulting in a sudden air loss or could develop a belt edge separation which could lead to partial or full tread/belt loss. Either condition increases the risk of a crash.

SEAT BELTS

General Motors, LLC (GM) is recalling certain 2020 Chevrolet Bolt EV and 2021 GMC Canyon and Sierra 1500, 2500 and 3500, Yukon, Yukon XL, Cadillac Escalade and Escalade ESV and Chevrolet Blazer, Camaro, Colorado, Equinox, Silverado 1500, 2500 and 3500, Suburban and Tahoe vehicles. Incorrect bolts may have been used at one or more fastening locations to secure the seat belts to the vehicle. If an incorrect bolt was used, the seat belt may not be properly attached to the vehicle.

Risk: If a seat belt assembly is not properly attached to the vehicle, the seat belt may not properly restrain an occupant in the event of a crash, increasing the risk of injury.

STEERING

My power steering completely failed. This is a safety issue and could have caused bodily harm. I have looked on line and I am not the only one with this issue, and as I investigated it shows that this issue was recall situation on earlier models. My truck is currently in the shop and looks like it will cost $5,000 to do the full repair.

UNKNOWN OR OTHER

I am experiencing a recurring issue with my 2021 GMC Sierra where the dashboard displays a “Shift to Park” warning even though the vehicle is already in Park. This typically occurs when I attempt to shut off the vehicle. The doors unlock as expected, confirming the truck is in Park, but the warning prevents me from turning off the ignition immediately. After a few seconds, the warning usually disappears, allowing me to shut off the truck. This issue is more frequent in cold weather, suggesting a temperature-sensitive electrical or mechanical fault. Based on research and community reports, this appears to be a known issue across multiple GM vehicles, often linked to a faulty micro switch or wiring harness in the shifter assembly. I am concerned about the safety implications, especially if the vehicle fails to shut off properly or if the issue worsens over time. GM has not issued a recall for this problem, and I believe it warrants further investigation due to its widespread nature and potential risk.

ELECTRICAL SYSTEM

I am experiencing a recurring issue with my 2021 GMC Sierra where the dashboard displays a “Shift to Park” warning even though the vehicle is already in Park. This typically occurs when I attempt to shut off the vehicle. The doors unlock as expected, confirming the truck is in Park, but the warning prevents me from turning off the ignition immediately. After a few seconds, the warning usually disappears, allowing me to shut off the truck. This issue is more frequent in cold weather, suggesting a temperature-sensitive electrical or mechanical fault. Based on research and community reports, this appears to be a known issue across multiple GM vehicles, often linked to a faulty micro switch or wiring harness in the shifter assembly. I am concerned about the safety implications, especially if the vehicle fails to shut off properly or if the issue worsens over time. GM has not issued a recall for this problem, and I believe it warrants further investigation due to its widespread nature and potential risk.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle inadvertently lost motive power. The contact was able to pull over to the shoulder of the roadway, where the vehicle failed to restart. No warning lights were illuminated. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired. After investigating the failure, the contact related the failure to NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); the VIN was included, but parts were not yet available. The manufacturer was not notified of the failure. The failure mileage was 60,000.

POWER TRAIN:AUTOMATIC TRANSMISSION:INTERNAL:SHAFT:OUTPUT

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 15 MPH, the vehicle briefly jerked and jolted, prompting him to discontinue driving the vehicle. The vehicle returned to normal functionality, but the failure became a regular occurrence. The check engine warning light was illuminated. The vehicle was taken to the dealer, who diagnosed failures with the output shaft speed sensor and the transmission control module. The vehicle was not repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was 89,000.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 15 MPH, the vehicle briefly jerked and jolted, prompting him to discontinue driving the vehicle. The vehicle returned to normal functionality, but the failure became a regular occurrence. The check engine warning light was illuminated. The vehicle was taken to the dealer, who diagnosed failures with the output shaft speed sensor and the transmission control module. The vehicle was not repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was 89,000.

ENGINE AND ENGINE COOLING

See attached document for complaint.

ENGINE AND ENGINE COOLING

See attached document for complaint. I am writing as the owner of a 2021 GMC Sierra 1500 equipped with the 6.2-liter engine that has recently been included in a significant recall. I've been advised that the engine may need to be replaced entirely. As you can imagine, this is extremely concerning given the scale of the defect and the vital role this truck plays i'n my dayto- day responsibilities.

ENGINE AND ENGINE COOLING

See attached document for complaint. This law firm represents [XXX] . [XXX] owns a GMC truck with VIN: xxxxxx which is subject to the above referenced recall. Please accept this letter as Mr. [XXX] 's written complaint due to his dealer's failure to remedy the defect covered under the above referenced recall. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure.

ENGINE

Complete engine failure on July 17, 2025, related to current recall for defective engine parts on 6.2L V8 L87 engine. Towed to dealer same day. Dealer continues to report no ETA available on replacement engine. Dealer has had possession of my unrepaired truck for 46 days now and counting.

UNKNOWN OR OTHER

Coolant control valve failure. Instantly reduces power on truck. National back order on parts. No remedy.

ENGINE

Coolant control valve failure. Instantly reduces power on truck. National back order on parts. No remedy.

POWER TRAIN

Have owned my 2021 GMC Sierra 1500 with the 3.0 Duramax for a year and the check engine light has come on multiple times for a "Coolant Control Valve" issue. The truck runs the fans at 100% and puts the truck into reduced power at least once a day. I have read that GM sometimes will not cover this repair under powertrain warranty even though it's an engine problem. Please fix this issue! To answer the previous questions, the coolant control valve is malfunctioning, and the truck is currently at the dealer being inspected. Yes the dealer has said this issue is common on these trucks (confirmed by National GMC in American Fork, Utah). Yes the check engine light has appeared multiple times. These issues started appearing in June 2025

ENGINE

Have owned my 2021 GMC Sierra 1500 with the 3.0 Duramax for a year and the check engine light has come on multiple times for a "Coolant Control Valve" issue. The truck runs the fans at 100% and puts the truck into reduced power at least once a day. I have read that GM sometimes will not cover this repair under powertrain warranty even though it's an engine problem. Please fix this issue! To answer the previous questions, the coolant control valve is malfunctioning, and the truck is currently at the dealer being inspected. Yes the dealer has said this issue is common on these trucks (confirmed by National GMC in American Fork, Utah). Yes the check engine light has appeared multiple times. These issues started appearing in June 2025

ENGINE

I receivd a recall on my 2021 GMC Denali 1500 , 6.2 engine Recall # N252494000. made an appointment with Carroll GMC, at 1455S. Tamiami Trail, Venice , Fl, on 7/29/25 at 11AM. I showed up for my appointment and they denied checking my truck on the recall stating they did not have the remedy to fix the problem so therefore they were not going to check my truck for the recall...... I have a trip coming up and now I a afraid to go on the highway in case my truck loses power and I get in an accident............ MY truck should have been checked for the recall regardless of the remedy to fix it..So at least I know weather it is safe to drive or not

LATCHES/LOCKS/LINKAGES:TAILGATE:LATCH

The contact owns a 2021 GMC Sierra 1500. The contact stated that while the vehicle was parked, the tailgate opened independently. No warning lights were illuminated. The contact stated that on a separate occasion, while the vehicle was parked at the residence, the contact approached the vehicle and the tailgate attempted to open independently. The contact moved the vehicle and turned off the engine. The tailgate attempted to open independently again. The contact moved the key fob away from the vehicle to prevent the tailgate from opening. No warning lights were illuminated. Most recently, the vehicle was parked at the residence in front of a toolbox, when the tailgate opened independently and dented the tailgate. The contact called the dealer; however, the vehicle was not diagnosed or repaired. Upon further investigation, the contact related the failure to Manufacturer Recall Number: N232426400. The manufacturer was not notified of the failure. The failure mileage was approximately 90,300.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated that the engine was previously replaced under warranty. The contact stated that the vehicle had been experiencing excessive oil consumption and required three quarts of oil every 30 days. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The contact stated that while driving 70 MPH, the vehicle shuddered abnormally and there was an abnormal metallic sound coming from the engine before the vehicle lost motive power. There was no warning light illuminated. The contact was able to pull over to the side of the road. The vehicle failed to restart and was towed to the residence. The local dealer was contacted and informed the contact that a service advisor would return the call. The vehicle was not diagnosed or repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the failure. The failure mileage was approximately 129,000.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (ENGINE AND ENGINE COOLING); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure.

POWER TRAIN

This vehicle experienced catastrophic engine failure while I was on vacation 400 miles from home. I have researched this failure and there is a class action lawsuit against GMC. My truck has been at the dealer for 25 days and still waiting for authorization from Fidelity Warranty Services. Considering it’s such a common problem I feel GMC should be paying for this. At the very least the warranty company is aware of this problem and purposely delaying the authorization to repair. I just bought a new camper which I cannot use. I am fisherman and cannot use my boat. My beach pass is also on the vehicle. So essentially my summer has been ruined by a company that produced a faulty vehicle and didn’t discord this information to me.

ENGINE

This vehicle experienced catastrophic engine failure while I was on vacation 400 miles from home. I have researched this failure and there is a class action lawsuit against GMC. My truck has been at the dealer for 25 days and still waiting for authorization from Fidelity Warranty Services. Considering it’s such a common problem I feel GMC should be paying for this. At the very least the warranty company is aware of this problem and purposely delaying the authorization to repair. I just bought a new camper which I cannot use. I am fisherman and cannot use my boat. My beach pass is also on the vehicle. So essentially my summer has been ruined by a company that produced a faulty vehicle and didn’t discord this information to me.

ENGINE

⸻ Background: •2021 GMC Sierra Denali – 6.2L V8 •VIN included in GM’s engine defect recall (connecting rod/crankshaft) •Recall status shows “No current remedy available” •Defect acknowledged by GM can cause “engine damage, loss of propulsion, or complete engine failure.” Timeline of Events: •~1 month ago – Truck began running rough with noticeable ticking/knocking noise. •Dealer could not schedule appointment for 3 weeks. •08/08/2025 – Dealer inspection confirmed failed lifters and damaged camshaft. •Repair estimate: $9,300 (see attached dealer estimate). Connection to Recall: •Lifter and camshaft are internal engine components dependent on the same lubrication and oiling system as the crankshaft/connecting rods cited in the recall defect. •The defect’s potential to contaminate oil and cause internal engine damage makes this failure consistent with recall-related damage.

LANE DEPARTURE: ASSIST

2021 GMC Sierra 1500 [XXX] miles 36,500. My childs seatbelt does not work and the lane keep assist does not work INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ELECTRICAL SYSTEM

2021 GMC Sierra 1500 [XXX] miles 36,500. My childs seatbelt does not work and the lane keep assist does not work INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

SEAT BELTS

2021 GMC Sierra 1500 [XXX] miles 36,500. My childs seatbelt does not work and the lane keep assist does not work INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

This recall has been coming for some time now its out and GM still has no plan or action. This is our only auto and my understanding if this issue happens it could cause loss of life. I am concerned for my wife driving to work every day and what happens if we want to take a trip. We need resolution on this. Apr 24,2025 Manufacturer Recall NumberN252494000 NHTSA Recall Number25V274 Recall StatusRecall Incomplete, remedy not yet available [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

POWER TRAIN

What component or system failed or malfunctioned, and is it available for inspection upon request? The Coolant Control Valve has stopped working. How was your safety or the safety of others put at risk? While driving the truck can overheat very quickly which can lead to dangerous temperatures as well as cause me to make an emergency stop on the highway to allow the truck to cool down. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, I have discussed with a dealership in person and independent mechanic who have confirmed the issue and confirmed it is a very common issue. So common that the only replacement part for the problem is backordered. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? No, they confirmed the issue without inspecting the vehicle because of how common it happens. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? There were no warnings before the issue. The issue happened and then the check engine light turned on as well as a "reduced engine power" message.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The contact stated that the check engine warning light was illuminated. The vehicle was taken to the dealer, where it was diagnosed with engine failure. The dealer informed the contact that there was no anticipated date for the recall repair parts availability. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 137,000.

FUEL/PROPULSION SYSTEM

Fuel tank leaking.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000(Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The contact stated that while driving 30 MPH, there was an abnormal knocking sound coming from the engine compartment, and the vehicle lost motive power. The contact was able to pull over to the side of the roadway. No warning light was illuminated. The vehicle was towed to a dealer, where it was determined that the engine needed to be replaced. The vehicle was repaired. The contact stated that prior to the engine failure, the transmission was replaced. The dealer was contacted regarding the recall remedy, but the dealer was unable to provide an estimated time of availability. The contact stated that the manufacturer exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the failure. The failure mileage was approximately 20,000. VIN tool confirms parts not available.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000(Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

ENGINE

Coolant Control Valve is faulty. Part number 24001355 for my GMC Diesel Sierra 1500. The check engine light goes on and sometimes the engine power will be cut in half to protect the engine. It can be inspected when needed. My truck cannot go as fast and the Engine fans sound very loud to cool down the engine. I was 3 hours away from my house when this happened the first time and I wasn’t sure I would make it home. I had to let the engine cool down for about 6 hours after I pulled off of the highway. This has happened two times so far and happens when the AC is on and sometimes when you use the remote start it won’t start the truck remotely and the check engine light goes on. The problem started in July 2025 with 51,000 miles. The engine control module code is P1098. I have asked my GMC dealership to look at the issue and they have told me that the part is backlogged for at least 2 months and they will not look at my truck until the part is available. I haven’t had any other issues with the engine so far and this was the first time a check engine light has gone on.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving approximately 40 MPH, the check engine warning light started flashing and the vehicle was shaking with a misfire coming from the engine. Additionally, there was black and greyish smoke coming from the tailpipe. The Roadside Assistance request message was displayed on the instrument cluster. The vehicle was taken to a dealer where it was diagnosed with a misfire. The vehicle was not repaired. The vehicle was taken to the residence, but the failure persisted. The vehicle was taken to an independent mechanic to be diagnosed, and it was determined that the lifter had dropped, and the engine needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was unknown.

VISIBILITY/WIPER

My rear electric window is leaking into my back seat area and the ceiling of the truck has water stains. It is coming from the roof and is leaking in 3 different areas. I am afraid I will now have mold in my car and I can’t have my grandchildren in the car to be safe for them. I had it checked at a local GMC dealer and I had to pay for a leak speacialist to verify and they confirmed the window has a leak. The leak started in April 2025 and has slowly gotten worse. The dealership said I will need to replace my back window to fix the issue and gave me an estimate of $1,100 and said my extended warranty will not cover this issue.

ELECTRICAL SYSTEM

The contact owns a 2021 GMC Sierra 1500. The contact stated that there was an abnormal change with the RPM. There were no warning lights illuminated. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The local dealer was contacted. The dealer received an email from the manufacturer, but the verbiage was incorrect to move forward with the repair. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The failure mileage was approximately 39,000. VIN tool confirms parts not available.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated that there was an abnormal change with the RPM. There were no warning lights illuminated. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The local dealer was contacted. The dealer received an email from the manufacturer, but the verbiage was incorrect to move forward with the repair. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The failure mileage was approximately 39,000. VIN tool confirms parts not available.

POWER TRAIN

I own a 2021 GMC Denali with a 6.2L V8 L87 engine and 45,500 miles. I have confirmed the presence of metal shavings in the oil and oil filter, indicating that the engine is beginning to fail. When I took the vehicle to my local dealership, I was informed that there is currently no fix for this issue and was advised to continue driving the vehicle. This poses a serious safety risk—not just to me and my family but also to others on the road. A sudden loss of power could lead to a dangerous accident, and I do not want to be responsible for something preventable that could harm innocent people. My concern is that GM is aware of this engine issue but has instructed me to keep driving the vehicle, despite the known defect. How can GM be allowed to avoid accountability for such a critical safety matter? If a fatal accident were to occur, would the responsibility fall on GM or the NHTSA for failing to act? It’s also troubling that GM continues to profit by selling new vehicles, including the 2025 models, with similar issues, all while neglecting to provide solutions for affected customers like me. I purchased this $80,000 truck in good faith, but now no dealer wants to trade or buy these trucks without me taking a significant financial loss—something GM should be responsible for. As a taxpayer, I find it unacceptable that we bailed out GM in the mid-2000s, yet they continue to disregard accountability for their actions. I urge the NHTSA to take this issue seriously. A specific deadline should be set for GM to resolve this issue, and they should face daily penalties for every day they fail to provide a fix. If no resolution is possible, full refunds should be mandated. Please address this issue promptly, as it affects real people’s safety and financial well-being every day.

FUEL/PROPULSION SYSTEM

I own a 2021 GMC Denali with a 6.2L V8 L87 engine and 45,500 miles. I have confirmed the presence of metal shavings in the oil and oil filter, indicating that the engine is beginning to fail. When I took the vehicle to my local dealership, I was informed that there is currently no fix for this issue and was advised to continue driving the vehicle. This poses a serious safety risk—not just to me and my family but also to others on the road. A sudden loss of power could lead to a dangerous accident, and I do not want to be responsible for something preventable that could harm innocent people. My concern is that GM is aware of this engine issue but has instructed me to keep driving the vehicle, despite the known defect. How can GM be allowed to avoid accountability for such a critical safety matter? If a fatal accident were to occur, would the responsibility fall on GM or the NHTSA for failing to act? It’s also troubling that GM continues to profit by selling new vehicles, including the 2025 models, with similar issues, all while neglecting to provide solutions for affected customers like me. I purchased this $80,000 truck in good faith, but now no dealer wants to trade or buy these trucks without me taking a significant financial loss—something GM should be responsible for. As a taxpayer, I find it unacceptable that we bailed out GM in the mid-2000s, yet they continue to disregard accountability for their actions. I urge the NHTSA to take this issue seriously. A specific deadline should be set for GM to resolve this issue, and they should face daily penalties for every day they fail to provide a fix. If no resolution is possible, full refunds should be mandated. Please address this issue promptly, as it affects real people’s safety and financial well-being every day.

ENGINE

I own a 2021 GMC Denali with a 6.2L V8 L87 engine and 45,500 miles. I have confirmed the presence of metal shavings in the oil and oil filter, indicating that the engine is beginning to fail. When I took the vehicle to my local dealership, I was informed that there is currently no fix for this issue and was advised to continue driving the vehicle. This poses a serious safety risk—not just to me and my family but also to others on the road. A sudden loss of power could lead to a dangerous accident, and I do not want to be responsible for something preventable that could harm innocent people. My concern is that GM is aware of this engine issue but has instructed me to keep driving the vehicle, despite the known defect. How can GM be allowed to avoid accountability for such a critical safety matter? If a fatal accident were to occur, would the responsibility fall on GM or the NHTSA for failing to act? It’s also troubling that GM continues to profit by selling new vehicles, including the 2025 models, with similar issues, all while neglecting to provide solutions for affected customers like me. I purchased this $80,000 truck in good faith, but now no dealer wants to trade or buy these trucks without me taking a significant financial loss—something GM should be responsible for. As a taxpayer, I find it unacceptable that we bailed out GM in the mid-2000s, yet they continue to disregard accountability for their actions. I urge the NHTSA to take this issue seriously. A specific deadline should be set for GM to resolve this issue, and they should face daily penalties for every day they fail to provide a fix. If no resolution is possible, full refunds should be mandated. Please address this issue promptly, as it affects real people’s safety and financial well-being every day.

UNKNOWN OR OTHER

The plastic frame of the rear sliding window failed. This has allowed water to enter the cabin, which can cause mold and other health issues. This seems to be a common issue with these trucks. My truck has a certified preowned warranty and GMC said they would only cover part of it. They charged me $400 as a deductible, which there should be no deductible per certified preowned warranty. I feel like GMC needs to put out an official recall.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle stalled, lost motive power, with smoke came from the engine compartment. There was no warning light illuminated. The vehicle was towed to the residence. The contact attempted to start the vehicle and noticed a knocking sound coming from the engine with the check engine warning light illuminated. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). The dealer was contacted and informed the contact that parts were not yet available. The dealer informed the contact that the vehicle had a Salvage Title and would not be repaired under the recall. The manufacturer was made aware of the failure, and a case was opened. The failure mileage was approximately 48,000. VIN tool confirms parts not available.

ENGINE

P1098 Code - Coolant Control Valve on/off/on/off.

ENGINE

The coolant control valve (Part # 24001355) has failed. Apparently this is the case with many vehicles and GM will not/can not get replacement parts. This should be a recall.

POWER TRAIN

AT AROUND 60,000 MILES I HAD EXPERIENCED SHUTTERING AND JERKING IN LOW GEARS AND THE VEHICLE SHOOTS FORWARD WHEN COMING TO A COMPLETE STOP. I WAS ABLE TO TAKE THE VEHICLE IN A SHORT TIME AFTER AND I WAS TOLD BY THE DEALERSHIP THAT IT NEEDED A TRANSMISSION FLUSH. I COMPLETED THE FLUSH AND AFTER A WEEK OR TWO IT STARTED DOING IT AGAIN. I TOOK IT TO A TRANSMISSION SHOP AND THEY ADVISED IT IS THE TRANSMISSION VALVE BODY THAT IS BAD. I BELIEVE THIS STARTED HAPPENING BEFORE MY WARRANTY WAS OUT BUT DUE TO ME BRINGING IT IN AFTER THE MILEAGE THEY WOULD NOT HONOR THE WARRANTY. THIS COULD CAUSE MULTIPLE HAZARDS AT STOPS AND WHILE DRIVING. NO WARNING LAMPS OR MESSAGE HAVE EVER APPEARED.

POWER TRAIN

The check engine light came on at one point. I took it to figure out why the check engine light was coming on and the scanner indicated that the NOX catalyst was below threshold. I researched it and it is a common issue. The check engine light eventually turned off after a couple of days. About 2 weeks later it came back on. I noticed as i was driving the coolant fans were running at 100% meaning that they were blowing long and hard. So I scanned it and it said that the engine coolant valve was at fault. This is also a common issue with the vehicle, particularly in the 2021 GMC Sierra 1500 3.0 Turbo Diesel. It is a faulty part and it costs thousands of dollars to replace. How can these two issues not be on a national recall by GM? They are too common and very expensive to repair. This issue is so common that now the valve is on a national back order. Meaning the parts may not be available for 30-120 days. The vehicle is not safe to drive with a bad engine coolant valve. I have now a rental car for the past 7 days while my truck sits waiting for a valve to arrive and pay thousands in repair just to drive it again.

ENGINE

The check engine light came on at one point. I took it to figure out why the check engine light was coming on and the scanner indicated that the NOX catalyst was below threshold. I researched it and it is a common issue. The check engine light eventually turned off after a couple of days. About 2 weeks later it came back on. I noticed as i was driving the coolant fans were running at 100% meaning that they were blowing long and hard. So I scanned it and it said that the engine coolant valve was at fault. This is also a common issue with the vehicle, particularly in the 2021 GMC Sierra 1500 3.0 Turbo Diesel. It is a faulty part and it costs thousands of dollars to replace. How can these two issues not be on a national recall by GM? They are too common and very expensive to repair. This issue is so common that now the valve is on a national back order. Meaning the parts may not be available for 30-120 days. The vehicle is not safe to drive with a bad engine coolant valve. I have now a rental car for the past 7 days while my truck sits waiting for a valve to arrive and pay thousands in repair just to drive it again.

ENGINE

When I started my truck in the morning I noticed the check engine light came on and my engine fan started running really loudly. I shut my truck off and let it sit for 5 minutes and restarted it in hopes the check engine light would not appear. Unfortunately it did come back on and the engine fan began running really loudly again. I drove the truck to the nearest mechanic and you could feel the truck was trying to counter the problem by forcing me to drive it in a lower speed. After taking it to a shop to get it scanned to see what the code was. The mechanic said it was reading code P1006 three times. He said this coolant system and is why my engine fan was triggered to run really loudly. But the engine was not over heating as all other indicators showed that temps were normal. The mechanic believes it could possibly just be a faulty wire. However after talking to GM he said if it is this coolant part that needs to be replaced, it could take up to months to fix as the part is on national backorder. Doing more research, it appears others have had this same problem and GM even knew shortly after this model was released that this would happen.

POWER TRAIN

wn a 2021 GMC Sierra 1500 6.2L (VIN: [XXX] ), which is now experiencing a severe misfire, engine ticking, and diagnostic code P318A. I’ve confirmed this issue is related to GM Recall N252494001 for engine connecting rod/crankshaft failure. However, I’ve been told my VIN has not yet been activated for recall repairs, and both the local dealership and GMC support have refused to escalate my case or offer assistance. This is a known safety issue, and I’m now at risk of total engine failure and significant financial loss while waiting for GM to act. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

wn a 2021 GMC Sierra 1500 6.2L (VIN: [XXX] ), which is now experiencing a severe misfire, engine ticking, and diagnostic code P318A. I’ve confirmed this issue is related to GM Recall N252494001 for engine connecting rod/crankshaft failure. However, I’ve been told my VIN has not yet been activated for recall repairs, and both the local dealership and GMC support have refused to escalate my case or offer assistance. This is a known safety issue, and I’m now at risk of total engine failure and significant financial loss while waiting for GM to act. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

My 2021 GMC Sierra 1500 with L87 engine, covered by recall 25V274. None of my local dealers are inspecting for this recall. This truck is my daily driver and I routinely drive on interstates for my work. GM has been slow to address this major manufacturing defect and has not remedied the problem. My truck is no longer worth what is was previously and is lowering trade in or sale value. I am requesting that GM buy back my vehicle due to ongoing safety risks and loss of value.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (ENGINE AND ENGINE COOLING); however, the part to do the recall repair was not yet available. The contact stated that while the vehicle was stopped, the vehicle idled intermittently. In addition, an abnormal sound was coming from the left side of the engine. The vehicle was not diagnosed or repaired. The local dealer was not contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the issue. The failure mileage was unknown. VIN tool confirms parts not available.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). The contact stated that while driving at approximately 50 MPH, there was a loud squeaking sound coming from the front driver’s side of the vehicle before the vehicle lost power. Simultaneously, the check engine warning light started blinking. The vehicle was pulled over to the side of the road and the sound became louder, before becoming a knocking sound. The vehicle was restarted, and the failure persisted. The vehicle was towed to the residence. The vehicle was not diagnosed or repaired, but a dealer stated that there was as recall associated with the VIN; however, parts were not yet available to repair the vehicle. The manufacturer was not notified of the failure. The failure mileage was approximately 128,000. VIN tool confirms parts not available.

FUEL/PROPULSION SYSTEM

Was informed from by GM that my vehicle is involved with a recall an still hasn't been repaired

ENGINE

Was informed from by GM that my vehicle is involved with a recall an still hasn't been repaired

POWER TRAIN

What component or system failed or malfunctioned, and is it available for inspection upon request? The valvetrain system failed due to broken rocker arms, which resulted in additional internal engine damage. This failure occurred under normal driving conditions. The affected components have not yet been discarded and are available for inspection upon request.How was your safety or the safety of others put at risk? The failure caused sudden engine misfiring and knocking, reducing engine power while I was operating the vehicle. This significantly compromised acceleration and response time, especially during merging and lane changes, which could have led to an accident. Any unexpected loss of power or engine instability at highway speeds poses a serious risk to myself, passengers, and other motorists.Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. The issue has been diagnosed and confirmed by an independent certified mechanic, who verified the broken rocker arms and resulting engine damage during inspection.Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others? The vehicle has not yet been inspected by the manufacturer, police, or insurance representatives. Only a certified independent mechanic has inspected the failure thus far.Were there any warning lamps, messages, or other symptoms of the problem prior to the failure, and when did they first appear? Yes. The check engine light appeared and the engine began running rough and producing a knocking sound. These symptoms occurred just prior to the confirmed failure and prompted me to stop driving the vehicle immediately and have it inspected. Given the seriousness of this issue and reports from other GMC 5.3L engine owners experiencing similar rocker arm failures, I urge the NHTSA to investigate this potential defect. It poses a real and significant safety risk.

ENGINE

What component or system failed or malfunctioned, and is it available for inspection upon request? The valvetrain system failed due to broken rocker arms, which resulted in additional internal engine damage. This failure occurred under normal driving conditions. The affected components have not yet been discarded and are available for inspection upon request.How was your safety or the safety of others put at risk? The failure caused sudden engine misfiring and knocking, reducing engine power while I was operating the vehicle. This significantly compromised acceleration and response time, especially during merging and lane changes, which could have led to an accident. Any unexpected loss of power or engine instability at highway speeds poses a serious risk to myself, passengers, and other motorists.Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. The issue has been diagnosed and confirmed by an independent certified mechanic, who verified the broken rocker arms and resulting engine damage during inspection.Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others? The vehicle has not yet been inspected by the manufacturer, police, or insurance representatives. Only a certified independent mechanic has inspected the failure thus far.Were there any warning lamps, messages, or other symptoms of the problem prior to the failure, and when did they first appear? Yes. The check engine light appeared and the engine began running rough and producing a knocking sound. These symptoms occurred just prior to the confirmed failure and prompted me to stop driving the vehicle immediately and have it inspected. Given the seriousness of this issue and reports from other GMC 5.3L engine owners experiencing similar rocker arm failures, I urge the NHTSA to investigate this potential defect. It poses a real and significant safety risk.

ENGINE

On Dec 27 I noticed a skip in my engine when I started the truck. I took the truck to Cronic Buick GMC on Jan 6 for an inspection. They reported to me that the engine failed.Seized up. I reported the incident to my extended warranty company Warranty Solutions. They refused to do the repair because I was late for an oil change in 2022. After 3 weeks and no cooperation I contacted GM customer service. I was assigned an agent that help initiate the engine repair . The repair was completed on April 12 (3 months after the failure). I paid $4600 out of pocket for a portion of the engine repair .

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000(Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The contact stated that while driving at approximately 60 MPH, the check engine warning illuminated and the vehicle stalled. The contact pulled to the side of the road and attempted to restart the vehicle, but the vehicle failed to restart. The vehicle was towed to the residence. The contact stated that the failure had previously occurred several times while driving. An unknown local dealer was contacted and informed the contact that the recall parts were not available. The vehicle was not diagnosed or repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was contacted and a voicemail message was left, but the manufacturer had not returned the contact's call. The failure mileage was approximately 70,000. VIN tool confirms parts not available.

ENGINE

Replacement part needed is COOLANT CONTROL VALVE according to diagnostics at local GM dealer service department after noting check engine light was on. YES, it is available for inspection. Told unsafe to drive as it would very likely overheat or worse. It has been in the shop for a month (as of June 11, 2025) awaiting a backordered part, which we’re told is a national backorder. No loaner vehicle available and told by service department that they have had another truck in for same problem for several months and that this problem is very common. PLEASE HELP us with getting the part needed!

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The contact stated that the vehicle was experiencing rough idling, with the RPM fluctuating while driving. The local dealer was contacted. The vehicle was not diagnosed or repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the issue. The failure mileage was approximately 32,000. VIN tool confirms parts not available.

POWER TRAIN

The coolant control valve is faulty and is on national backorder causing months of my truck sitting in the shop. This is not an isolated issue. GM is claiming it is not covered under warranty, but the part design is clearly a serious issue.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 75 MPH, the vehicle jerked and downshifted to overdrive. The message "Engine Power Reduced" was displayed on the instrument panel. The driver depressed the accelerator pedal, but the vehicle failed to exceed 4 MPH. The vehicle was taken to the dealer, where it was diagnosed that the valve body failed, which caused the transmission to fail. The vehicle was repaired. While the contact was driving home after the vehicle was picked up, the vehicle jerked and hesitated. The dealer was contacted and informed the contact that if the check engine warning light becomes illuminated the vehicle could be diagnosed. After several days, the check engine warning light illuminated, and the vehicle was taken to the dealer where it was diagnosed that the shutter valve had failed and needed to be replaced. The vehicle was repaired. The contact stated that the failure persisted. The contact received NHTSA Campaign Number: 24V797000 (POWER TRAIN). The vehicle was repaired; however, the failure persisted. The manufacturer was made aware of the failure and offered the contact assistance with the transmission repair. The failure mileage was approximately 119,000.

ENGINE AND ENGINE COOLING

See attached document for complaint.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated that upon starting the vehicle, there was an abnormal knocking sound coming from the engine. The abnormal sound ceased once the vehicle had accelerated; however, the abnormal sound returned while the vehicle was idling. The check engine warning light was illuminated. The vehicle was taken to the dealer where it was diagnosed that the ball bearing caused a misfire, and two cam lifters needed to be replaced. The vehicle was repaired. The contact picked up the vehicle and on the way home, the engine failed. The contact took the vehicle back to the dealer. The technician test drove the vehicle with the contact as a passenger, and the check engine warning light illuminated. In addition, there was an abnormal sound coming from the engine. The vehicle failed to accelerate as intended while depressing the accelerator pedal. The contact was informed that the engine failed and needed to be replaced along with the fuel body system. The contact was informed that as per GMC, the oil needed to be changed to an oil with a thicker viscosity. The fuel body was replaced, and the oil was changed. The manufacturer was made aware of the failure and offered the contact an amended warranty. The contact was informed that GMC had elected to participate in the procedures under the Song Beverly Act. The failure mileage was approximately 50,000.

ENGINE

The coolant control valve on my truck is causing issues. From doing research, this is an ongoing issue with the 3.0 duramax. The part is on nationwide backorder and I cannot drive my vehicle in reduced engine power because the only way I can get to work is by taking the interstate. It is madness that GM has not issued a recall or done anything to rectify this issue. Many GMC owners are paying on vehicles that they are unable to drive which is assanine. This part needs to be readily available due to the NUMEROUS complaints that have already been submitted in regards to this part.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated that upon starting the vehicle, the vehicle was idling abnormally, prompting the contact to turn off the vehicle. The contact stated that the check engine warning light was illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the lifter in cylinder #4. The contact stated that the lifter had collapsed into the engine, causing damages to the engine and camshaft. The vehicle was repaired. The manufacturer was not notified of the failure. The failure mileage was 98,000.

POWER TRAIN

My 2021 GMC Sierra 1500 Diesel Truck is displaying the Check Engine Light which I was told by the local Mount Vernon GMC Dealership is a failed Temperature Control Valve affecting the transmission. I also get a warning message of "Reduced Engine Power". I am told that it is OK to drive the vehicle but at reduced power. The dealership told me they ordered a replacement part which is covered under warranty on May 7, 2025, but showed on "Back Order". Every time I call to follow up on the status, I'm told it is still on "Back Order", and they cannot do anything to improve the delivery. Why does a customer, owning a "Denali" truck under warranty, can't get the problem resolved? I have a recall notice from GMC dated January 2025 about this very problem and have shown it to GMC dealerships during regular services, and still have the problem. Since I have bought this truck, I have experienced a failed right running board that cost $1,500 to repair a few months ago which is failing again. The driver side mirror now vibrates when I put the truck into drive after being in reverse, and I cannot get any idea on when this transmission valve problem will be fixed which is causing me serious delays in using the truck to pull a trailer. Prior to this problem I had the dealership replace my brakes which required 2 follow-up repairs due to the "GMC original rotors" being warped that required machining to make them not vibrate which to me, now makes them "used". This means I paid full price for "repaired" parts! I thought that by buying a GMC "Denali" 1500 Sierra truck I was buying the "top of the line" in pick-up trucks but now finding out it's a lemon. I love the truck, but not the problems. What do I need to do to get this fixed? [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

It started with a emergency brake light coming on, shortly (2 miles) later it started misfiring on cylinder #1 after replacing coil pack plug wire and plug. It then started smoking bad out of the exhaust. I knew GM was having recalls on the 6.2 engines so I hauled it to the dealer. They told me it was a bad engine and since it had aprox.62,000 miles on it and no recall it wasn't covered. Since then the dealer called the factory service rep. and he agreed to replace the engine at a 50% reduction in the price, but had no idea when they could get me a replacement engine. After a few days of research on my part I called the dealer again to get a price on how much it was going to cost me? The owner of the dealership ask me to give him a few more days to ask the rep. if he would agree to 100%. My problem now is I don't have it to drive, I can't sell it. and no idea how long it will be before it can be repaired. Plus I am still making payments on it. It is available for inspection at the dealer. If I had of continued to drive, it could have locked up causing a catastrophic accident. In my research it looks like these problems started in 2019 not late 2020 when mine was built. NC has lemon law complaints going back to 2019 that have been paid out. I currently own a #1 2007 GMC Yukon Denali 6.2 with aprox.389,000 miles and only replaced the transmission recently. #2 A 2008 GMC Sierra Denali 6.2 with 279,052 miles, new transmission. #3 A 2011 GMC Yukon Denali 6.2 with 234,361 miles and #4 a 2017 Cadillac Escalade 6.2 with aprox. 102,000 miles. All of these are working and driving on a daily bases. I have a lot of faith in these 6.2 engines until now, I will no longer be buying any more of these engines even though 1 out of 5 aint bad. Thank you for your consideration and for what you do. [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated that occasionally while attempting to start the vehicle, the engine hesitated to turn over. The contact stated that the failure progressed, and the vehicle no longer started as needed. The check engine warning light was illuminated. The contact stated that two local dealers were contacted; however, the contact was advised that to diagnose or repair the vehicle, might take several months. The vehicle was towed to a local independent mechanic, where it was diagnosed with camshaft sensor failure. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 83,000.

ENGINE AND ENGINE COOLING:ENGINE:CRANK/CAMSHAFT POSITION SENSOR

The contact owns a 2021 GMC Sierra 1500. The contact stated that occasionally while attempting to start the vehicle, the engine hesitated to turn over. The contact stated that the failure progressed, and the vehicle no longer started as needed. The check engine warning light was illuminated. The contact stated that two local dealers were contacted; however, the contact was advised that to diagnose or repair the vehicle, might take several months. The vehicle was towed to a local independent mechanic, where it was diagnosed with camshaft sensor failure. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 83,000.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (ENGINE AND ENGINE COOLING); however, the part to do the recall repair was not yet available. The contact stated that while driving 70 MPH, the vehicle failed to accelerate as intended while depressing the accelerator pedal. No warning lights were illuminated. The contact stated that several minutes later the vehicle functioned as designed. The local dealer was contacted; however, the vehicle was not diagnosed or repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the issue. The failure mileage was approximately 38,000. VIN tool confirms parts not available.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (ENGINE AND ENGINE COOLING); however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

ENGINE

Safety recall, unsafe

SERVICE BRAKES

On March 10, 2025, I was driving down a residential street, about 40 mph, when the "Brake System Failure, 42 miles top speed," indicator light came on. Seconds later, I was approaching a stop sign and pressed down on the brake pedal. The brakes failed and the brake pedal went directly down to the floor. Luckily there were no other vehicles around and i was able to coast through the stop sign. I continued to coast until the truck stopped on its own and I was able to shift the gear into park. I've checked for recalls on my truck for this issue and did not find any. There is a similar issue with the GMC 2500 and 3500 series. Perhaps the issue is broader than expected.

FUEL/PROPULSION SYSTEM

Engine experiences missing when accelerating in lower speeds ...also now, and since driving for a few thousand miles, f umes are entering cabin frequently and causing nausea, 'headaches and burning of mouth, lips and eyes .....all the time. My youngest granddaughter got sick and so did my oldest son just this past weekend! As far as I know , police or dealership never inspected , nor did they acknowledge it! No warning lamps appeared

UNKNOWN OR OTHER

Engine experiences missing when accelerating in lower speeds ...also now, and since driving for a few thousand miles, f umes are entering cabin frequently and causing nausea, 'headaches and burning of mouth, lips and eyes .....all the time. My youngest granddaughter got sick and so did my oldest son just this past weekend! As far as I know , police or dealership never inspected , nor did they acknowledge it! No warning lamps appeared

ENGINE

Engine experiences missing when accelerating in lower speeds ...also now, and since driving for a few thousand miles, f umes are entering cabin frequently and causing nausea, 'headaches and burning of mouth, lips and eyes .....all the time. My youngest granddaughter got sick and so did my oldest son just this past weekend! As far as I know , police or dealership never inspected , nor did they acknowledge it! No warning lamps appeared

POWER TRAIN

In December of 2024 the engine started not being able to reach full power. This would happen intermittently and there would be a check engine light that would come on when this was happening. In January of 2025 I had the code pulled up by a mechanic at a local shop and this mechanic actually spoke to the service manager of the GMC dealership who said it was covered under the 100,000 mile power train warranty. I took it to the dealership who then told me the diesel mechanic was backed up and I would have to schedule repair for February. I had also received a recall notice in the mail for another issue so asked about taking of both things at the same time. I made the appointment for mid-February so had to deal with reduced engine power for several weeks.The dealership had my truck for several days and a recall was fixed and I thought the reason for the reduced engine power had been fixed also. I had received a phone call from the service representative about an issue that would cost over $1200 that I declined. I did not realize that this was actually for the main issue. I was still thinking the reduced engine power was under warranty. I got my truck back but then the next day the check engine light came on again and the engine power was reduced again. I immediately called the service representative who then told me only the recall had been fixed and that the reason for the reduced engine power was not fixed because I had declined the service. I was totally confused and didn’t understand what happened. This is when I was told that the reason for the reduced engine power was due to a coolant control valve, which was not under the powertrain warranty. I pushed the issue and wanted answers as to why the service manager himself told the mechanic that it was under warranty and was told that the service manager is not a technician and they rely on what the technician says is the problem. And this problem was not covered. I finally gave in and got it fixed and paid $1788.

UNKNOWN OR OTHER

When I am in park my engine shuts off the light goes from green to orange which indicates it’s still on electrically. I have to turn on/off my vehicle multiple times for it to turn off fully. It’s an intermittent problem.

POWER TRAIN

coolant control valve failure activating check engine light, reduced power mode and fan running continuously. Truck has been in the shop for 3 weeks already with no part available.

ENGINE

I heard a ticking in the engine and noticed multiple warning lights in the dashboard. I called the GMC dealer and was told the next opening was several weeks away. I was also told that it would be OK to drive the vehicle which I did (~10 miles) and parked the truck in my driveway until I could get the truck in for a diagnostic evaluation. The service department at the GMC dealer where the vehicle was purchased identified a defective camshaft/lifter as the source of the noise and lights. The service manager recommended either an engine rebuild at their shop or purchase a replacement motor from the GMC inventory network. The serial # of the old motor is: 126852545. The serial # of the new motor is: 40208378. The cost of the new motor, replacement of required fluids and parts and labor was $12,360. 100% of the repair was paid by myself. The .pdf of the service record (RO #: 9189240) exceeds the 10 MB limit and cannot be uploaded. I have a hard copy if needed. The dealership where the vehicle was purchased and serviced is: TULLEY Buick - GMC - BMW - Mazda P.O. Box T 147 Daniel Webster Highway South Nashua, New Hampshire 03060 (603) 888-0550 www.tulley.com

ENGINE

I had an engine warning warning light on my dash around May 5th. A notice of reduced speed also lit up my dash while I was on the freeway. I scheduled a service for May 15th and was told the engine coolant flow control valve needed to be replaced. I was also told there was a backlog of other vehicles waiting for the same part. It has been over a month and I am still unable to drive my truck which I use for work.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at various speeds, the check engine warning light illuminated, and the engine fan activated and operated at a very high velocity. Additionally, the message "Engine Power Failure" message was displayed, and the vehicle stalled. The vehicle was taken to the local dealer who diagnosed that the engine coolant control valve was faulty and needed to be replaced. The contact was informed that the parts were on backorder and no repairs were performed. The manufacturer was not yet contacted. The failure mileage was 45,000.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated upon starting the vehicle and shifting to drive(D) in the morning, the transmission hesitated to shift to second gear and then shifted harshly. There was no warning light illuminated. The vehicle was taken to the dealer, where it was test-driven, but the failure could not be duplicated. The contact stated that the failure occurred once a day on first start-up of the vehicle and upon shifting to drive(D). The vehicle was taken back to the dealer over the weekend, and the dealer was able to duplicate the failure on first start-up of the vehicle and upon shift to drive(D). The dealer related the failure to TSB Number: 16-NA-361; and informed the contact the manufacturer had not made a repair available. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to file a complaint. The failure mileage was unknown.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at various speeds, the check engine warning light illuminated, and the engine fan activated and operated at a very high velocity. Additionally, the message "Engine Power Failure" message was displayed, and the vehicle stalled. The vehicle was taken to the local dealer who diagnosed that the engine coolant control valve was faulty and needed to be replaced. The contact was informed that the parts were on backorder and no repairs were performed. The manufacturer was not yet contacted. The failure mileage was 48,000.

ENGINE

My Truck has been consuming oil since new, latest documented consumption test was 1.25 quarts in 1967 miles. GM dealership said that is normal and no further diagnosis is required. GM says acceptable consumption is 1 quart per 2,000 miles. This truck has a 6.2L engine that is not under the current recall ( N252494000 ). The engine problems affect more vehicles that the current recall and should be investigated.

UNKNOWN OR OTHER

Dealer keeps ignoring engine knock noise states its normal , mpg is down dramatically . Shift to park , vehicle only has 34k miles and dealer does not want to repair under warranty due to vehicle being a 2021 Battery keeps draining for no reason , new battery added still does the same thing

ENGINE

Dealer keeps ignoring engine knock noise states its normal , mpg is down dramatically . Shift to park , vehicle only has 34k miles and dealer does not want to repair under warranty due to vehicle being a 2021 Battery keeps draining for no reason , new battery added still does the same thing

FUEL/PROPULSION SYSTEM

- #5 injector failure, no. - Once the injector failed, the vehicle would violently shake when trying to accelerate. - Yes, was not covered under factory warranty but replaced by third-party extended warranty. -Yes, replaced by the dealership. -No warnings prior, once the injector failed warning for brake system check and vehicle mileage limits set in warning.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was unavailable. The dealer was not contacted and confirmed that parts were not yet available. The manufacturer was not made aware of the failure. The contact had not experienced a failure. VIN tool confirms parts not available.

POWER TRAIN

received my truck back after replacement of the front transmission pump and idle gear, the same day the transmission had horrible down shifts, sometimes it would just downshift into neutral and bounce off the rev limiter. the service advisor told me that my transmission had to "relearn" my driving habits when I called him and would take 200-400 miles.. i drove it one more day and drove it back to the dealer to have them drive it. the agreed that something was wrong, but didn't know what and had to contact gm engineers. 2 days later they told me that the valve body needs to be replaced. I dropped it off to find out that it had been ordered with zero ETA of when they will receive it.. so now im stuck with a loaner and no ETA on when parts will be available.

ENGINE

Engine seized while at idle speed and has to be replaced. It was a catastrophic event, but not covered under the current recall for 6.2L L87 engines.

WHEELS

• The airbag system failed to deploy during a collision that resulted in the total loss of the vehicle. Additionally, the vehicle was operating with a 17” spare tire (undersized compared to the standard 20” wheels), which may have contributed to the accident. The vehicle has been totaled and is currently in the possession of the insurance company, but may be available for inspection upon request. • Despite the severity of the collision, none of the airbags deployed, which could have resulted in serious injury if the circumstances were different. The use of an undersized 17” spare tire may have affected the vehicle’s stability, braking, or performance, contributing to the crash. • No. The vehicle was declared a total loss and has not been evaluated for defect reproduction by a dealer or service center. However, I am aware of related recalls and lawsuits regarding both improper spare tire sizing and airbag non-deployment in 2020–2021 GMC Sierra models. • The vehicle has been inspected by the insurance company during the total loss evaluation. A police report was also completed at the scene of the accident. To my knowledge, the manufacturer (GM) has not inspected the vehicle at this time. • No. There were no warning lights, messages, or symptoms prior to the crash. The vehicle gave no indication of any issue with the airbags or tire compatibility leading up to the accident. I was involved in an accident in my 2021 GMC Sierra. At the time, the vehicle was operating with a 17” spare tire installed, which I later discovered may be significantly undersized compared to the standard 20” wheels. During the crash, the impact was severe enough to total the vehicle, but none of the airbags deployed. Fortunately, there were no injuries, but I believe the non-deployment of the airbags represents a critical product safety defect. I’ve since learned that GM has recalled similar vehicles for incorrect spare tires, and that lawsuits have been filed regarding calibration issues.

AIR BAGS

• The airbag system failed to deploy during a collision that resulted in the total loss of the vehicle. Additionally, the vehicle was operating with a 17” spare tire (undersized compared to the standard 20” wheels), which may have contributed to the accident. The vehicle has been totaled and is currently in the possession of the insurance company, but may be available for inspection upon request. • Despite the severity of the collision, none of the airbags deployed, which could have resulted in serious injury if the circumstances were different. The use of an undersized 17” spare tire may have affected the vehicle’s stability, braking, or performance, contributing to the crash. • No. The vehicle was declared a total loss and has not been evaluated for defect reproduction by a dealer or service center. However, I am aware of related recalls and lawsuits regarding both improper spare tire sizing and airbag non-deployment in 2020–2021 GMC Sierra models. • The vehicle has been inspected by the insurance company during the total loss evaluation. A police report was also completed at the scene of the accident. To my knowledge, the manufacturer (GM) has not inspected the vehicle at this time. • No. There were no warning lights, messages, or symptoms prior to the crash. The vehicle gave no indication of any issue with the airbags or tire compatibility leading up to the accident. I was involved in an accident in my 2021 GMC Sierra. At the time, the vehicle was operating with a 17” spare tire installed, which I later discovered may be significantly undersized compared to the standard 20” wheels. During the crash, the impact was severe enough to total the vehicle, but none of the airbags deployed. Fortunately, there were no injuries, but I believe the non-deployment of the airbags represents a critical product safety defect. I’ve since learned that GM has recalled similar vehicles for incorrect spare tires, and that lawsuits have been filed regarding calibration issues.

STEERING

While traveling on the interstate the vehicle lost all propulsion and started to rapidly decelerate. Shortly after propulsion was lost the engine turned off completely affecting the steering and braking of the vehicle. The vehicle was towed to the GMC dealership that we purchased it from. repairs have not begun so I assume it would be available for inspection. We were traveling on a three lane interstate up a grade at 80 MPH. Had I not been able to safely get the vehicle stopped and out of traffic or had we lost control going down a grade we would not have been able to stop the vehicle and there would've potentially been a catastrophic accident most likely resulting in injury or death. No the dealership has not diagnosed the failure physically. The service writer did suggest that it sounds like the failure reported from the recall not being addressed. I did contact the dealer about the recall on Saturday May6th. At which time I was informed there was not a solution for the vehicle for my vehicle at that time. There were no warning prior to the incident. After the engine stopped operating there was a warning produced on the instrument panel that read "Engine Oil Hot" and the instrument panel no longer registered any oil pressure.

SERVICE BRAKES

While traveling on the interstate the vehicle lost all propulsion and started to rapidly decelerate. Shortly after propulsion was lost the engine turned off completely affecting the steering and braking of the vehicle. The vehicle was towed to the GMC dealership that we purchased it from. repairs have not begun so I assume it would be available for inspection. We were traveling on a three lane interstate up a grade at 80 MPH. Had I not been able to safely get the vehicle stopped and out of traffic or had we lost control going down a grade we would not have been able to stop the vehicle and there would've potentially been a catastrophic accident most likely resulting in injury or death. No the dealership has not diagnosed the failure physically. The service writer did suggest that it sounds like the failure reported from the recall not being addressed. I did contact the dealer about the recall on Saturday May6th. At which time I was informed there was not a solution for the vehicle for my vehicle at that time. There were no warning prior to the incident. After the engine stopped operating there was a warning produced on the instrument panel that read "Engine Oil Hot" and the instrument panel no longer registered any oil pressure.

ENGINE

While traveling on the interstate the vehicle lost all propulsion and started to rapidly decelerate. Shortly after propulsion was lost the engine turned off completely affecting the steering and braking of the vehicle. The vehicle was towed to the GMC dealership that we purchased it from. repairs have not begun so I assume it would be available for inspection. We were traveling on a three lane interstate up a grade at 80 MPH. Had I not been able to safely get the vehicle stopped and out of traffic or had we lost control going down a grade we would not have been able to stop the vehicle and there would've potentially been a catastrophic accident most likely resulting in injury or death. No the dealership has not diagnosed the failure physically. The service writer did suggest that it sounds like the failure reported from the recall not being addressed. I did contact the dealer about the recall on Saturday May6th. At which time I was informed there was not a solution for the vehicle for my vehicle at that time. There were no warning prior to the incident. After the engine stopped operating there was a warning produced on the instrument panel that read "Engine Oil Hot" and the instrument panel no longer registered any oil pressure.

VISIBILITY/WIPER

I don't believe this needs to have an investigation, but i would like it documented and brought to GM's attention for future body designs. I have never had as many rocks/debris hit my windshield as I have with this truck. I have had one chip in a windshield in 30+ years of driving, until this truck where I have had several that needed repairs, and this last one has created a Crack large enough where my windshield needs replaced. It may be bad luck, but I've talked to multiple other Sierra owners and most of them have had the same issue. A couple have had the windshield replaced almost yearly. Please at minimum inform GM engineers to possibly determine the cause (I assume aerodynamics) so they can incorporate the flaw (if there really is one) into future designs. The photo I included happened almost immediately after the impact. The crack has grown several inches since as expected.

POWER TRAIN

Reached the 100,000 mile mark and the truck started shuddering. Took it to the dealership and they tell me the torque converter is coming apart and I need a new transmission.

ENGINE

My truck has a known recall from GMC which results in total loss of propulsion. It has not failed yet, but this is dangerous to me, my family/kids, and potentially others on the road. I have made multiple attempts to speak with GMC about the issue and also my local dealer. Neither group will provide concrete information as to when they can look at/service my truck even though there is a known remedy - [XXX] I brought my car into the dealer December of 2024 for brakes and also a rattling noise since it was uncharacteristic. Noises can be indicative of this larger problem (which I know now and didn't then) but they "didn't hear a rattle" and the "condition could not be duplicated" which is patently false since it still makes the noise/has gotten worse. Since then, I have taken the following actions: - I called and spoke with the local dealer service team on 5/5 - was told since it's showing incomplete, no remedy available there was nothing they could do - Spoke with GMC on 5/5 - they directed me to the local dealership - Made an appointment online on 5/10 to get my truck serviced and to check for this problem - They immediately called me first thing on Monday 5/12 to cancel my appointment and again tell me there is nothing they can do about this issue - I have continued to express my safety concerns to both parties - I spoke to GMC today, 5/30 and was told that there is no timeline for the issue (with my VIN) even though the remedy is known - An appointment is scheduled on 6/12 with my local dealership, but if I recall status hasn't changed, they will not check for this problem INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

POWER TRAIN

My truck has a known recall from GMC which results in total loss of propulsion. It has not failed yet, but this is dangerous to me, my family/kids, and potentially others on the road. I have made multiple attempts to speak with GMC about the issue and also my local dealer. Neither group will provide concrete information as to when they can look at/service my truck even though there is a known remedy - [XXX] I brought my car into the dealer December of 2024 for brakes and also a rattling noise since it was uncharacteristic. Noises can be indicative of this larger problem (which I know now and didn't then) but they "didn't hear a rattle" and the "condition could not be duplicated" which is patently false since it still makes the noise/has gotten worse. Since then, I have taken the following actions: - I called and spoke with the local dealer service team on 5/5 - was told since it's showing incomplete, no remedy available there was nothing they could do - Spoke with GMC on 5/5 - they directed me to the local dealership - Made an appointment online on 5/10 to get my truck serviced and to check for this problem - They immediately called me first thing on Monday 5/12 to cancel my appointment and again tell me there is nothing they can do about this issue - I have continued to express my safety concerns to both parties - I spoke to GMC today, 5/30 and was told that there is no timeline for the issue (with my VIN) even though the remedy is known - An appointment is scheduled on 6/12 with my local dealership, but if I recall status hasn't changed, they will not check for this problem INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

POWER TRAIN

front idler gear for the transmission pump failed at 39500 miles. was fixed under GMC warranty. but now after getting the truck back the transmission has extremely harsh down shifts. still waiting for GM to figure out what to do next..

ENGINE

The truck ever since of bought it has been nothing but issues. Starting with the fuel pump issues then electrical issues and most recently the coolant flow control valve. This is my work truck and now I’m out of a truck with no loaner and the dealership has no eta.

POWER TRAIN

The truck ever since of bought it has been nothing but issues. Starting with the fuel pump issues then electrical issues and most recently the coolant flow control valve. This is my work truck and now I’m out of a truck with no loaner and the dealership has no eta.

ENGINE

I’m filing a complaint regarding GM Recall N232404000/N232404002, which affects the L87 6.2L V8 engine in my 2021 GMC Sierra 1500 AT4. This recall is tied to a serious defect that can cause sudden loss of propulsion due to internal engine failure. My vehicle has shown symptoms since purchase — including engine ticking, unusual noises, and low oil levels — all documented by dealership service records. GM originally instructed dealers to replace engines based on build date, which made sense given the nature of the defect. But now they’ve changed the remedy midstream. Instead of replacing potentially defective engines, they perform a PicoScope test, and if it “passes,” the only action taken is replacing the oil with a different grade. This does nothing to resolve the underlying issue. How does a manufacturer go from replacing engines due to internal failure risks to simply changing the oil and calling the problem solved? This undermines the purpose of a safety recall and places future liability on the consumer. A known internal mechanical defect cannot be fixed with an oil change, yet GM is closing out cases this way. Now I’m stuck with a vehicle I can’t fully trust — one that may still fail unexpectedly — and possibly face diminished resale or trade-in value due to an engine that other buyers will view as unreliable or patched over. GM is leaving owners with the long-term risk while clearing their books of liability. I urge the NHTSA to investigate whether this revised approach truly meets federal recall standards.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was unavailable. The dealer was contacted; however, the contact was informed that parts were not yet available for the recall repair. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

ENGINE

Unknown There is a recall on the this model but with different motor but when I took mine in they said it was a.manufactured defect but I was out of warranty because I purchased it cash and didn't get extended warranty now im having to replace and pay for a head and new engine over 10,000 when vehicle doesn't even have 70,000 miles it started with a engine light going on amd off for 2 weeks then it just stopped working It's too coincidental that the sister truck make n model to this had a recall for exactly what is wrong with mine

ENGINE

We have the 6.2 liter GM engine that has lost propultion. We are not covered in the recall and are 30,000 miles above the milage warranty, but still within the time portion of the warranty. GM payment assisitance has only offered us $1600 to help with replacing our engine. The dealership told me their warranty parts price was higher, so it really didn't offset any cost. This is our ONLY vehicle for our small appliance repair business. Our vehicle was manufactured at the plant in Canada where all the other faulty engines were manufactured. Please consider widening the recall to include our vehicle.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the low oil warning light illuminated. The vehicle was taken to the dealer but was not diagnosed or repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 67,600.

POWER TRAIN

Engine has stopped a couple of times at low speeds, Was able to restart and continue. Engine will occasionally make a "straining / Dieseling sputtering sound" when execellerating from low speeds or Stop. Transmission will make strange and strained shifts from time to time. This is reaccruing problem that comes and goes over the last approximately 2 yrs since about 9000 miles to current approx 25000 miles.

ENGINE

Engine has stopped a couple of times at low speeds, Was able to restart and continue. Engine will occasionally make a "straining / Dieseling sputtering sound" when execellerating from low speeds or Stop. Transmission will make strange and strained shifts from time to time. This is reaccruing problem that comes and goes over the last approximately 2 yrs since about 9000 miles to current approx 25000 miles.

ENGINE

My GM 6.2L V8 engine has seized in less than 100K Miles. Thankfully not whilst driving and being potentially harmful to myself or others with the catastrophic failure. This problem is being widely report and continually occurring. GM is saying that I am not included in the massive recall for this, However NHTSA notes the vin range as NR and indicates incidents are still occurring. Seems to be a real lemon situation here and even bigger a letdown to uphold consumer safety.

POWER TRAIN

The transmissions in this as well as several other models of GM as well as Ford products with these transmissions are known to have major issues. My particular vehicle has major transmission shipping issues that started right around 90,000 miles or so. It started with a hard shift occasionally and has now progressed to a consistant hard shift, as well as a major shudder issue in the 35-45 mph range as well as the 65-75mph range ( when shifting into applicable gears) this has gotten worse over the last few weeks. These GM/Ford collaboration transmissions have been faulty from their inception and are well known to start malfunctioning in the 80-120,000 mile range. Please recall these transmissions so that consumers are not faced with thousands of dollars in repairs in vehicles that should last well beyond the short life span of the transmissions. I have been quoted 62-6500.00 for a replacement as there is no rebuilding these transmissions according to the mechanics I have consulted...(some have cited part availability issues as a reason). This has been a well reported problem with these vehicles/ transmissions for years now with many complaints and issues about the faulty transmissions. Just google it. I don't understand why theu have yet to be recalled.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, there was an abnormal rattling sound coming from the vehicle, with several unknown warning lights illuminated. The vehicle was driven to the residence. The vehicle was taken to the dealer where it was diagnosed with cam shaft and lifter failures. The contact was informed that the cam shaft and the lifters needed to be replaced. The vehicle was not repaired. In addition, the contact stated that when the vehicle was purchased in 2020, the failure had occurred; however, the repair was covered under warranty. The manufacturer was not made aware of the failure. The failure mileage was approximately 7,000.

LATCHES/LOCKS/LINKAGES

The contact owns a 2021 GMC Sierra 1500. The contact stated that the rear tailgate panel buttons had deteriorated causing water intrusion into the panel, and the buttons became inoperable when pressed, and the rear tailgate would not open. The vehicle was taken to the local dealer who replaced the rear tailgate panel, and the vehicle was repaired. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 20,000.

ENGINE

code P1098. Engine light comes on, power is reduced, coolant fan runs on high. Temp gauge fluctuates. This last for 20 minutes or so. The engine then returns to normal. After a few days the engine trouble light goes off. This happens every several weeks. Parts are backlogged and I understand this is a common problem with this engine. I have 64000 on it.

ENGINE

While driving vehicle started running rough and exhaust was white from tail pipes, could not accelerate and warning lights were flashing. Limped to dealership and diagnosed with a bent rod and had to tear both sides of engine apart and replace heads on both sides due to bulletin for Gmail at 7500 miles. Why is this vehicle not part of the recall to protect my investment?

ENGINE

While the vehicle is traveling at highway speeds it is misfiring and sputtering, giving the feeling of a hard shift. When the vehicle is idling, the engine is sputtering like it’s going to shut off. If the truck were to shut down, as it seems to be trying to do, this could be deadly at highest speeds or intersections. The vehicle has been at a dealer since January 2025. They claimed to have fixed it but upon paying over $1200 and picking it up from the dealer, the problem persisted. We had to take it back to the dealer within 5 minutes of picking it with zero repairs and no estimated time of repairs ever since. No warning lights appeared at all.

ELECTRICAL SYSTEM

GM has has a known issue with a switch/sensor placed at the base of the shifter that causes the “shift to park” error message that prevents the electrical system from shutting down when the vehicle is physically in park and the engine is turned off, In fact, GM has issued a recall for several different models in which a “shift to park” error message is displayed because of the poor design; however, they continue to see the same issue occur but claim it is not a warranty issue (unless it occurs within 3 year/36,000 mile time frame. This is not an issue that can be caused by owner misuse, and I believe that GM should be held liable for repairs given that the issue is, and has been, known for several years now.

ENGINE

So there is recall already for the engine but I’m not part of it which is weird cause my engine has been acting weird which I’m trying to take to dealer ship but they don’t want it due to I not being in the recall list. I have the engine 6.2 LTI have an 2021 GMC Sierra Denali

VEHICLE SPEED CONTROL

The engine coolant flow control valve position sensor is faulty. I brought mt truck in to my dealership and I have been waiting for over a month to get the issue fixed because “the part is on backorder”. This issue makes my truck sound like a jet engine because it makes the truck think overheating and causes the fan to come on at full blast. After drivinf for awhile it goes into “ reduced engine power mode” which is totally unsafe because it reduces the horse power to that of a lawn mower. It takes about 30 seconds to get from 0-60, so merging onto freeways or in conditions where you need extra speed its completely useless and increases the scenario of being rear ended, immensely.

FUEL/PROPULSION SYSTEM

The engine coolant flow control valve position sensor is faulty. I brought mt truck in to my dealership and I have been waiting for over a month to get the issue fixed because “the part is on backorder”. This issue makes my truck sound like a jet engine because it makes the truck think overheating and causes the fan to come on at full blast. After drivinf for awhile it goes into “ reduced engine power mode” which is totally unsafe because it reduces the horse power to that of a lawn mower. It takes about 30 seconds to get from 0-60, so merging onto freeways or in conditions where you need extra speed its completely useless and increases the scenario of being rear ended, immensely.

POWER TRAIN

The engine coolant flow control valve position sensor is faulty. I brought mt truck in to my dealership and I have been waiting for over a month to get the issue fixed because “the part is on backorder”. This issue makes my truck sound like a jet engine because it makes the truck think overheating and causes the fan to come on at full blast. After drivinf for awhile it goes into “ reduced engine power mode” which is totally unsafe because it reduces the horse power to that of a lawn mower. It takes about 30 seconds to get from 0-60, so merging onto freeways or in conditions where you need extra speed its completely useless and increases the scenario of being rear ended, immensely.

POWER TRAIN

VEHICLE IS DIAGANOSED WITH A COOLANT CONTROL VALVE ISSUE. VEHICLE IS CURRENTLY AT A GM DEALER AWAITNG REPLACEMENT PART AND PART IS ON BACK ORDER FOR AN UNDERTEMINED AMOUNT OF TIME. IT IS WIDELY KNOWN THIS IS A COMMON PROBLEM WITH THIS MAKE AND YEAR MODEL OF VEHICLE. THIS MATTER PUTS AN UNDUE HARDSHIP ON ME AS A VEHICLE OWNER. WITH NO KNOWN ETA FOR THIS PART I STAND TO BE OUT OF USE OF THIS VEHICLE FOR A LONG TIME. GM NEEDS TO BE MORE ACCOUNTABLE AND ATTENTIVE TO THEIR CUSTOMERS AT A TIME LIKE THIS.

ENGINE

The camshaft cover in pre 2021 3.0L Duramax motors is leaking oil/def internally causing oil loss. This is something GM has noted in their TSB pages but has not issued a recall over. This is a hazard to emissions, oil consumption, and the def system. Also could result in premature engine failure.

ENGINE

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ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 75 MPH, the vehicle lost automotive power. The contact pulled over onto the side of the road, and upon parking on the side of the road, the message "Shift to Neutral" was displayed. The contact shifted into neutral, and the vehicle was restarted. The vehicle was taken to a local dealer, and was diagnosed, and the contact was informed that no cause for the failure was found. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 24,453.

LANE DEPARTURE: ASSIST

El motor de mi camioneta falló por completo empezó a hacerle unos ruidos muy fuertes dentro del motor con solo 80,000 millas es del 2021 la compré el año pasado no llegó ni un año de uso una camioneta que supuestamente era muy buenas Estaba en el momento de lo sucedido estaba con mi mujer y mi hijo en el auto regresábamos de un restaurante acá en Miami y la camioneta se paró de pronto La camioneta fue inspeccionada por la garantía extendida la cual no asumió la reparación Luego del problema si salieron luces amarillas y rojas en la pantalla de mi camioneta

POWER TRAIN

El motor de mi camioneta falló por completo empezó a hacerle unos ruidos muy fuertes dentro del motor con solo 80,000 millas es del 2021 la compré el año pasado no llegó ni un año de uso una camioneta que supuestamente era muy buenas Estaba en el momento de lo sucedido estaba con mi mujer y mi hijo en el auto regresábamos de un restaurante acá en Miami y la camioneta se paró de pronto La camioneta fue inspeccionada por la garantía extendida la cual no asumió la reparación Luego del problema si salieron luces amarillas y rojas en la pantalla de mi camioneta

ENGINE

El motor de mi camioneta falló por completo empezó a hacerle unos ruidos muy fuertes dentro del motor con solo 80,000 millas es del 2021 la compré el año pasado no llegó ni un año de uso una camioneta que supuestamente era muy buenas Estaba en el momento de lo sucedido estaba con mi mujer y mi hijo en el auto regresábamos de un restaurante acá en Miami y la camioneta se paró de pronto La camioneta fue inspeccionada por la garantía extendida la cual no asumió la reparación Luego del problema si salieron luces amarillas y rojas en la pantalla de mi camioneta

ENGINE

In February of 2025 my check engine light came on while i was at work. Went to the local auto zone to have the code read and it. Right after that i drove straight to Gay Family Auto. along the way there was a jolt followed by a stall The car behind me nearly re ended me. i made it to the dealership after inspection i was told i blew a rod and had metal shavings due to an engine failure. Up to this point i had no indication of any issues or dash board warnings. i was told i needed to provide all prof of oil changes which i did. after two months i get my truck back from GMC with a new motor. The new motor is now under recall for doing the exact same thing as my old motor. GM basically took out a faulty motor replaced it with a new one in hopes nothing happens. I reached out to GM and they told me to take it to a dealership for inspection. The dealership told me they wont touch it til GMC sends a solution. im currently driving a truck that could possiably fail again

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated that the vehicle was experiencing excessive oil consumption. The low oil pressure warning light was illuminated. The vehicle was taken to the dealer, but the failure could not be duplicated. The vehicle was taken to the dealer several times, where an oil consumption test was performed. The contact stated that the oil consumption test was not completed. The contact stated that while driving 55-60 MPH, the contact noticed an abnormal oil odor, and the low oil pressure warning light was illuminated. The contact pulled over. The contact then noticed that a significant amount of oil was leaking onto the ground. The vehicle was towed to the residence of the contact's brother. The contact stated that upon inspecting the vehicle, the contact became aware that oil was leaking from the oil pan. The vehicle was towed to the contact's residence, where the contact added oil to the vehicle. The vehicle was taken to Beck & Masten GMC Coastal (200 US-77, Robstown, TX 78380), where the rear main seal gasket was replaced; however, the failure persisted. The vehicle was taken back to the dealer, where it was diagnosed that the alternator and the crankshaft hoses had failed due to excessive oil leaks. The dealer charged a fee for the alternator and the crankshaft hoses replacement. The dealer informed the contact that the rear main seal gasket replacement was covered. The dealer related the oil leak to the oil pressure. The vehicle was not repaired. The manufacturer was notified of the failure, and cases were filed; however, no further assistance was provided. The failure mileage was 44,000.

POWER TRAIN

While driving on the highway the engine died forcing me to change lanes to cross traffic and coast to a stop on the shoulder. It was dangerous and unexpected. It would not restart so I had to have it towed. Inspection revealed the bearings had gone bad in the engine and the engine would have to be replaced. I had to wait 2 and half months for an engine.

ENGINE

While driving on the highway the engine died forcing me to change lanes to cross traffic and coast to a stop on the shoulder. It was dangerous and unexpected. It would not restart so I had to have it towed. Inspection revealed the bearings had gone bad in the engine and the engine would have to be replaced. I had to wait 2 and half months for an engine.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, the vehicle lost motive power, with several unknown warning lights illuminated. The vehicle was able to restart but went into LIMP Mode. The vehicle was towed to the dealer, where it was diagnosed that the cylinder head had failed and needed to be replaced. The vehicle was repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline for assistance. The approximate failure mileage was 43,000.

STEERING

I was driving approximately 25-30 mph coming over an overpass moving into the right hand lane when my truck right front end failed. The steering and brakes locked up for approximately 50’ until I hit the curb for the sidewalk and stopped. I safely exited the vehicle checked the left side of my truck for damage and didn’t find anything. I walked around the back of my truck and came to the passenger side where I found my right front wheel and tire completely broken away from both upper and lower control arms, the ball joint broke and failed as well as the brake line. If I was driving on the highway at 65-75 this catastrophic failure could have resulted in a fatal collision. The night before my [XXX] daughter and I returned from her outdoor Ed trip in Sausalito and we drove an hour home to Napa on [XXX] and [XXX] . I thank god this didn’t happen with her in the car on the highway. I had my truck towed to Jimmy Vasser Chevy in Napa so I can see if the extended warranty will cover the repairs since it was an obvious catastrophic failure of the whole right front end. It’s still sitting there. The extended warranty inspector came Friday to take pictures of the damage INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

WHEELS

I was driving approximately 25-30 mph coming over an overpass moving into the right hand lane when my truck right front end failed. The steering and brakes locked up for approximately 50’ until I hit the curb for the sidewalk and stopped. I safely exited the vehicle checked the left side of my truck for damage and didn’t find anything. I walked around the back of my truck and came to the passenger side where I found my right front wheel and tire completely broken away from both upper and lower control arms, the ball joint broke and failed as well as the brake line. If I was driving on the highway at 65-75 this catastrophic failure could have resulted in a fatal collision. The night before my [XXX] daughter and I returned from her outdoor Ed trip in Sausalito and we drove an hour home to Napa on [XXX] and [XXX] . I thank god this didn’t happen with her in the car on the highway. I had my truck towed to Jimmy Vasser Chevy in Napa so I can see if the extended warranty will cover the repairs since it was an obvious catastrophic failure of the whole right front end. It’s still sitting there. The extended warranty inspector came Friday to take pictures of the damage INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

POWER TRAIN

Was driving vehicle on freeway at normal speeds and the vehicle lost propulsion. Engine was off and vehicle said to shift to neutral and restart. I was able to exit the freeway safely (barely) to the median. Vehicle would not restart. It has the L87 engine which is under recall. Vehicle is at dealership submitted under the recall. I am being told there is "no remedy" and "no parts" and given no timeframe for any fix to be completed. I am still liable for the payments, insurance and this is our only vehicle in a single father of three family.

ENGINE

The vehicle will crank and not start. Dealership said they cannot replicate the fault. Same problem occurred after with dealership not helping. I am a US Soldier currently stationed in Germany and continue to have the same problem every 2months. It will crank and not start. The truck will start on the second attempt after cranking for about 20seconds. The continued issue can permanently damage expensive repair parts that I will not be able to afford. I know I am not the only one with the same issue as I have talked to others and have no solution for this.

ENGINE

My vehicle suddenly stopped working in the middle of an intersection. A screen notification prompted me to restart it, so I pulled over safely, as there were no other vehicles nearby. However, I worry about the potential danger if this had happened on a freeway. After waiting, I tried restarting the vehicle, but it still wouldn’t work. The next day, I received an email from Carfax about an open recall for my vehicle due to engine issues, matching the symptoms I was experiencing. I scheduled an appointment for 4/28, and had the vehicle towed to Elk Grove Buick GMC. At GMC, they couldn’t offer immediate solutions, needing to diagnose the vehicle first. This process took about four days. During this time, I was advised to contact GM, as the vehicle was affected by the recall. I submitted a case to GM on April 28th, requesting compensation for a rental or loaner vehicle, a truck for my business needs. Without it, my business operations would suffer, leading to revenue loss. The dealership’s diagnosis found the engine seized due to a failed bearing. GM contacted me about the recall, initially mentioning the lemon law and a potential buyback, which I hadn’t considered. After I expressed a desire to repair the vehicle, they contacted the dealership for more information. GM later clarified that the vehicle wasn’t covered under the recall, citing the cause and symptoms as not meeting the recall’s criteria. This seems contradictory, as a failed engine doesn’t necessarily contradict the recall. GM stated they couldn’t provide a remedy, leaving me responsible for repair costs, and noted my vehicle’s 70,000 miles exceeded the power train warranty. Recall claims dealerships will inspect and, if necessary, repair or replace the engine. It’s confusing why my vehicle isn’t covered for repairs or assistance under this recall despite the engine failure. What is the law in terms of warranty as I was under the impression that warranty status is irrelevant in an active recall vehicle.

ENGINE

Coolant Control Valve (ccv) on these vehicles are notorious for breaking down/ becoming non-operative. I have been waiting for a part for months.

POWER TRAIN

I was coming home after work, before I got home I stopped at the gas station to fill up my tank, after I filled up my tank I start driving home but while on my way home my truck wasn’t speed as I expected and it only goes maximum of 10mph and I was confused, I stop and check my truck see what happens but there is no sign since there was no sign I get on my truck and start driving to home, after I got home I was trying to revers parking and that’s when I realized my truck wouldn’t reverse. I thought of if it happened while I was driving on highway and my truck stopped on the middle of highway I could have lost my life. I called the dealer and the dealer told me it might be because of the engine then next day I took it to the shop and they couldn’t figure until couple days later and it took them around 2-3 weeks to replace my transmission. Luckily I had the power train warranty when I bought the vehicle and it don’t cost anything. If I didn’t have that power train warranty everything will come out of my pocket, the cost was around $6-7k.

ENGINE

I was coming home after work, before I got home I stopped at the gas station to fill up my tank, after I filled up my tank I start driving home but while on my way home my truck wasn’t speed as I expected and it only goes maximum of 10mph and I was confused, I stop and check my truck see what happens but there is no sign since there was no sign I get on my truck and start driving to home, after I got home I was trying to revers parking and that’s when I realized my truck wouldn’t reverse. I thought of if it happened while I was driving on highway and my truck stopped on the middle of highway I could have lost my life. I called the dealer and the dealer told me it might be because of the engine then next day I took it to the shop and they couldn’t figure until couple days later and it took them around 2-3 weeks to replace my transmission. Luckily I had the power train warranty when I bought the vehicle and it don’t cost anything. If I didn’t have that power train warranty everything will come out of my pocket, the cost was around $6-7k.

UNKNOWN OR OTHER

We NEVER RECEIVED A RECALL NOTICE FYI . This vehicle has been serviced consistently.never an issue. Driving on [XXX] very busy! Truck literally stopped in the middle of the freeway in a very bad location. Desert. Noon. Kids with us. Could have died. Preliminary eval: engine seized, piston rod failure. Not sure the rest - we have to tow it home first. Failed while traveling. Please call for more information if needed. [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

We NEVER RECEIVED A RECALL NOTICE FYI . This vehicle has been serviced consistently.never an issue. Driving on [XXX] very busy! Truck literally stopped in the middle of the freeway in a very bad location. Desert. Noon. Kids with us. Could have died. Preliminary eval: engine seized, piston rod failure. Not sure the rest - we have to tow it home first. Failed while traveling. Please call for more information if needed. [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

I've noticed rough or jerky gear shifting when accelerating, rough and reduced propulsion, loss of power. Dealership repaired power torque converter but the truck continue to have the same symptoms.

POWER TRAIN

I've noticed rough or jerky gear shifting when accelerating, rough and reduced propulsion, loss of power. Dealership repaired power torque converter but the truck continue to have the same symptoms.

UNKNOWN OR OTHER

I've noticed rough or jerky gear shifting when accelerating, rough and reduced propulsion, loss of power. Dealership repaired power torque converter but the truck continue to have the same symptoms.

STEERING

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at slow speeds and accelerating out of the neighborhood, the vehicle experienced a loss of automotive power, with the check engine and EPS warning lights illuminated. The contact was able to drive the vehicle back to the residence. The vehicle was then towed to a local dealer where the vehicle was diagnosed, and the contact was informed that the engine had failed and needed to be replaced. The vehicle was repaired. The manufacturer was notified of the failure. The approximate failure mileage was 103,000.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at slow speeds and accelerating out of the neighborhood, the vehicle experienced a loss of automotive power, with the check engine and EPS warning lights illuminated. The contact was able to drive the vehicle back to the residence. The vehicle was then towed to a local dealer where the vehicle was diagnosed, and the contact was informed that the engine had failed and needed to be replaced. The vehicle was repaired. The manufacturer was notified of the failure. The approximate failure mileage was 103,000.

ENGINE

Engine failed GM made me pay for a new one. Second engine failed due to mechanics did not change out radiator. I now have a third motor with a recall. This vehicle has cost me a lot of out of pocket expenses, I believe GM owes me for the depreciated value plus lost wages. Maybe a buy back I'm not sure.

UNKNOWN OR OTHER

The transmission is constantly whirring, rattling, and screeching.

ENGINE

The transmission is constantly whirring, rattling, and screeching.

POWER TRAIN

While driving my truck with my wife and two young boys, the truck engine completely shut off while operating it. We were stuck in the middle of the road and had to cautiously wait until we could move the vehicle out of the way. The engine locked up. Now they are trying to repair the engine with the same exact engine that is on recall and potentially put me and my family in the same dangerous position.

ENGINE

While driving my truck with my wife and two young boys, the truck engine completely shut off while operating it. We were stuck in the middle of the road and had to cautiously wait until we could move the vehicle out of the way. The engine locked up. Now they are trying to repair the engine with the same exact engine that is on recall and potentially put me and my family in the same dangerous position.

ELECTRICAL SYSTEM

While driving my truck with my wife and two young boys, the truck engine completely shut off while operating it. We were stuck in the middle of the road and had to cautiously wait until we could move the vehicle out of the way. The engine locked up. Now they are trying to repair the engine with the same exact engine that is on recall and potentially put me and my family in the same dangerous position.

ENGINE

Vehicle has less than 64,000 miles and seems to be having engine issues. ESC message with engine power reduced. Cannot even drive the vehicle any longer. Cannot get it into a shop for a month and will have to have it towed.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed and making a turn, the vehicle made a loud banging sound and the vehicle shut off. No warning light was illuminated. The vehicle was towed to an independent mechanic, who determined that the engine had failed and needed to be replaced. The vehicle was not repaired. The contact related the failure to NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the VIN was not included in the recall. The manufacturer was not made aware of the failure. The failure mileage was approximately 80,000.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact was notified of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The local dealer was made aware of the issue and confirmed that parts were not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 65 - 70 MPH, there was a knocking sound coming from the vehicle and the vehicle shut off. There were unknown warning lights illuminated. The vehicle was towed to an unknown location. The local dealer was contacted. The vehicle was not diagnosed or repaired. The vehicle was taken to an independent mechanic who determined that there was a solid engine bottom and bearing failure. The contact was informed that the engine needed to be replaced. The vehicle was repaired. but the failure recurred, and the vehicle failed to start. The manufacturer was contacted and informed of the failure. The failure mileage was approximately 83,000.

ENGINE

I wanted to reach out to see if there is anything in addition to the lemon law. I bought a 2021 GMC Sierra with 38,000 miles on it around March of last year. There was a motor defect which was covered by the warranty. I was driving and it stopped in the middle of the road so I had to safely maneuver out of the main road. The truck was towed to my house with 45,184 miles on it, until the GMC dealership could take it in to inspect. They did take a while to get me a rental because everything was backed up. They said they could rent me out a truck due to not being their brand and that it only covers a certain amount. It got taken in by the dealership on 7/15/2024 and ended up getting the truck back repaired on 8/27. I did get the truck back and have been having it, I am just worried about it breaking down or anything of that nature. I just wanted to know if there is any further process I should do or since they repaired it there should be no issue.

ENGINE

First engine blown 31,904 miles, Lifter failure. Replaced with re-manufactured engine. Second engine failure at 68,000 miles, Piston rod failure. Piston blew thru engine block and engine bay caught on fire.

ENGINE

I had purchased a 2021 GMC Sierra equipped with the 6.2 liter motor in October of 2021. Within two weeks, my engine was experiencing problems. There was no service lights on the dash, and my truck suddenly shut off while on a busy road. I was able to coast to the side of the road, however it was a driving lane with no shoulder which made the situation dangerous. I was able to restart the engine after some time, and eventually get the vehicle off of the roadway, thankfully I got out of the driving lane without being struck by another vehicle. The truck had approximatley 1000 miles at this time and was brand new. I ended up needing a complete engine replacement due to failed crank bearings and connecting rods. I was told it was a crankshaft issue. After the complete motor replacement, sometime during the next year I was experiencing oil burning issues. On this second motor, a GM dealer had to completley rebuild the top end of the motor and install new piston rings. This is now a total of two motor failues in under 30,000 miles.

VEHICLE SPEED CONTROL

Tried to accelerate and heard a loud pop and the truck didn’t accelerate. Pretty much went idle in the middle of the road. The check engine light, the traction control light, and the ABS light all came on. I would press on the gas and it would rev but nothing would happen till a few seconds later the RPM’s would shoot up and you could tell it was trying to get going but didn’t very slowly and I would hear a clicking noise every time it was around the second gear. It put my children and myself in danger because traffic was heavy with vehicles going 70+mph merging into one lane. Took it to a dealership and they stated it was the the push rod and camshaft were damaged and all 16 lifters should be replaced and camshaft also. No, the vehicle has not been inspected by any of those except a car dealership and a mechanic. This problem first appeared the day it happened and continued after. Even took it to a mechanic and had all 16 lifters changed and problem still persists. Spent over $6,000 on a brand new truck and it is still undrivable because every time you get in to drive it the cylinder #2 misfires.

POWER TRAIN

Tried to accelerate and heard a loud pop and the truck didn’t accelerate. Pretty much went idle in the middle of the road. The check engine light, the traction control light, and the ABS light all came on. I would press on the gas and it would rev but nothing would happen till a few seconds later the RPM’s would shoot up and you could tell it was trying to get going but didn’t very slowly and I would hear a clicking noise every time it was around the second gear. It put my children and myself in danger because traffic was heavy with vehicles going 70+mph merging into one lane. Took it to a dealership and they stated it was the the push rod and camshaft were damaged and all 16 lifters should be replaced and camshaft also. No, the vehicle has not been inspected by any of those except a car dealership and a mechanic. This problem first appeared the day it happened and continued after. Even took it to a mechanic and had all 16 lifters changed and problem still persists. Spent over $6,000 on a brand new truck and it is still undrivable because every time you get in to drive it the cylinder #2 misfires.

ENGINE

Tried to accelerate and heard a loud pop and the truck didn’t accelerate. Pretty much went idle in the middle of the road. The check engine light, the traction control light, and the ABS light all came on. I would press on the gas and it would rev but nothing would happen till a few seconds later the RPM’s would shoot up and you could tell it was trying to get going but didn’t very slowly and I would hear a clicking noise every time it was around the second gear. It put my children and myself in danger because traffic was heavy with vehicles going 70+mph merging into one lane. Took it to a dealership and they stated it was the the push rod and camshaft were damaged and all 16 lifters should be replaced and camshaft also. No, the vehicle has not been inspected by any of those except a car dealership and a mechanic. This problem first appeared the day it happened and continued after. Even took it to a mechanic and had all 16 lifters changed and problem still persists. Spent over $6,000 on a brand new truck and it is still undrivable because every time you get in to drive it the cylinder #2 misfires.

POWER TRAIN

See attached vehicle repair orders/Carfax/vehicle registration. The trucks transmission has been slipping/jerking hard since I pulled off the lot at dealer ship. Its burning oil no leaks has been doing so since the day I drove off the lot at dealership. I have asked to fix or address and problem still exist. They sold vehicle as everything was working The Left head light wasn’t working the day I drove off the lot didn’t notice until I got home I reached back out to dealer to explain and said light had a short in kept truck for almost a week said the were going to replace the head light and never did. The remote start wasn’t working the same day i purchased the truck but sold it as everything is working. I went to try it as I was getting ready to leave dealership and did nothing. Then I discovered the fog lights were missing, and dealer said oh there was never any in the truck but if you read the service paper work there was lights in truck. Took truck back to address the issues the next day or so after purchase I was told to bring truck back the following week. All the conditions still exist and I should not be having any of these issues as the sold vehicle nothing wrong. They even had an October inspection saying everything was SAT but I get in truck no fog lights and left head lamp is not working but they performed an 360 inspection….yeah no way… This truck is doing the same as my 2021 chevy Silverado but there is nothing wrong with vehicle according to dealership. Sold A Lemon if you asked me… ***Highlighted in yellow is a recall that the dealership has not done nor can they find anything on the recall**** *****Power train**** Recall date 2024-10-24 Recall no. 24V797000 General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel en

ENGINE

See attached vehicle repair orders/Carfax/vehicle registration. The trucks transmission has been slipping/jerking hard since I pulled off the lot at dealer ship. Its burning oil no leaks has been doing so since the day I drove off the lot at dealership. I have asked to fix or address and problem still exist. They sold vehicle as everything was working The Left head light wasn’t working the day I drove off the lot didn’t notice until I got home I reached back out to dealer to explain and said light had a short in kept truck for almost a week said the were going to replace the head light and never did. The remote start wasn’t working the same day i purchased the truck but sold it as everything is working. I went to try it as I was getting ready to leave dealership and did nothing. Then I discovered the fog lights were missing, and dealer said oh there was never any in the truck but if you read the service paper work there was lights in truck. Took truck back to address the issues the next day or so after purchase I was told to bring truck back the following week. All the conditions still exist and I should not be having any of these issues as the sold vehicle nothing wrong. They even had an October inspection saying everything was SAT but I get in truck no fog lights and left head lamp is not working but they performed an 360 inspection….yeah no way… This truck is doing the same as my 2021 chevy Silverado but there is nothing wrong with vehicle according to dealership. Sold A Lemon if you asked me… ***Highlighted in yellow is a recall that the dealership has not done nor can they find anything on the recall**** *****Power train**** Recall date 2024-10-24 Recall no. 24V797000 General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel en

ELECTRICAL SYSTEM

See attached vehicle repair orders/Carfax/vehicle registration. The trucks transmission has been slipping/jerking hard since I pulled off the lot at dealer ship. Its burning oil no leaks has been doing so since the day I drove off the lot at dealership. I have asked to fix or address and problem still exist. They sold vehicle as everything was working The Left head light wasn’t working the day I drove off the lot didn’t notice until I got home I reached back out to dealer to explain and said light had a short in kept truck for almost a week said the were going to replace the head light and never did. The remote start wasn’t working the same day i purchased the truck but sold it as everything is working. I went to try it as I was getting ready to leave dealership and did nothing. Then I discovered the fog lights were missing, and dealer said oh there was never any in the truck but if you read the service paper work there was lights in truck. Took truck back to address the issues the next day or so after purchase I was told to bring truck back the following week. All the conditions still exist and I should not be having any of these issues as the sold vehicle nothing wrong. They even had an October inspection saying everything was SAT but I get in truck no fog lights and left head lamp is not working but they performed an 360 inspection….yeah no way… This truck is doing the same as my 2021 chevy Silverado but there is nothing wrong with vehicle according to dealership. Sold A Lemon if you asked me… ***Highlighted in yellow is a recall that the dealership has not done nor can they find anything on the recall**** *****Power train**** Recall date 2024-10-24 Recall no. 24V797000 General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel en

FUEL/PROPULSION SYSTEM

Motor seized up while going around 65mph. Truck lost all power and would not start brought to dealer and they said that it was the crankshaft bearings and something with the connecting rods, the deal told me that they don’t know what to do and is waiting on GM. There is a recall for these issues but no fix. I’m just waiting for the dealer to tell me what’s next but they don’t even know.

ENGINE

Motor seized up while going around 65mph. Truck lost all power and would not start brought to dealer and they said that it was the crankshaft bearings and something with the connecting rods, the deal told me that they don’t know what to do and is waiting on GM. There is a recall for these issues but no fix. I’m just waiting for the dealer to tell me what’s next but they don’t even know.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving approximately 55 MPH, the vehicle suddenly experienced a loss of automotive power. During the failure, the message "Shift into Neutral to Restart" was displayed. The vehicle was later towed to the local dealer, who diagnosed that the piston bearings had seized, causing damage to the engine. The engine was replaced along with the radiator, oil cooler and oil cooler hoses, intake manifold, mega fuse, and starter. The manufacturer was notified of the failure. The contact was informed that the VIN was recently included in the NHTSA Campaign Number: 25V274000 (ENGINE AND ENGINE COOLING). The contact stated that the vehicle had experienced the failure listed in the recall. The failure mileage was 122,691.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated that there was an abnormal ticking sound coming from the vehicle while idling. There was no warning light illuminated. The vehicle was taken to an independent mechanic to be diagnosed. The contact was then notified of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The local dealer was not made aware of the issue. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The failure mileage was approximately 33,000. VIN tool confirms parts not available.

POWER TRAIN

Engine power reduced, could not accelerate, fuel pump issue and was bucking the engine Went to dealer and complained as gmc not working to help me, dealer fixed issue but said no other complaints out there and car was fixed, gmc called me several times and keeps saying no issues with the vin associated. The car was fixed but I am stuck with a truck that is probably not saleable once these issues continue. This issue happened initially with 30 k on it and dealer could not find the issue and this times at 61500 happened again

FUEL/PROPULSION SYSTEM

Engine power reduced, could not accelerate, fuel pump issue and was bucking the engine Went to dealer and complained as gmc not working to help me, dealer fixed issue but said no other complaints out there and car was fixed, gmc called me several times and keeps saying no issues with the vin associated. The car was fixed but I am stuck with a truck that is probably not saleable once these issues continue. This issue happened initially with 30 k on it and dealer could not find the issue and this times at 61500 happened again

ENGINE

Engine power reduced, could not accelerate, fuel pump issue and was bucking the engine Went to dealer and complained as gmc not working to help me, dealer fixed issue but said no other complaints out there and car was fixed, gmc called me several times and keeps saying no issues with the vin associated. The car was fixed but I am stuck with a truck that is probably not saleable once these issues continue. This issue happened initially with 30 k on it and dealer could not find the issue and this times at 61500 happened again

POWER TRAIN

was getting on the interstate whenever i hit 70 mph just heard a hard knock in the engine and truck was driving rough. the truck it self dropped to 60mph. before it occurred there was no check engine light on or anything. after i had the dash light up with engine light, brake light, stability light. about a week later took it to the dealer they said it was fuel injectors they replaced it took them about 2weeks but the problem wasn’t resolved but then stated it was the lifters which they said it almost common for this to happened. so i took it somewhere else to get replaced and they said yes it was the lifters and i needed to replace the camshaft because when the lifters go out it will damage the camshaft. all they did to diagnose my problem was hear it was ticking and the knocks also with the codes from the dealer diagnosis. after my repairs it was expensive least to say

ENGINE

was getting on the interstate whenever i hit 70 mph just heard a hard knock in the engine and truck was driving rough. the truck it self dropped to 60mph. before it occurred there was no check engine light on or anything. after i had the dash light up with engine light, brake light, stability light. about a week later took it to the dealer they said it was fuel injectors they replaced it took them about 2weeks but the problem wasn’t resolved but then stated it was the lifters which they said it almost common for this to happened. so i took it somewhere else to get replaced and they said yes it was the lifters and i needed to replace the camshaft because when the lifters go out it will damage the camshaft. all they did to diagnose my problem was hear it was ticking and the knocks also with the codes from the dealer diagnosis. after my repairs it was expensive least to say

ENGINE

Engine light came on, went to the dealership where I bought the truck less then two weeks prior. The Chevy dealership ran diagnostic test on it. They said it was the Engine Coolant Control Valve. This is a common problem with the 3.0 Duramax diesel engine. I belong to a group on Facebook with the same truck as mine. they are all having the same issue. We are waiting for a recall. the part is on back order and cost $300 just for the part plus labor. I bought the extended warranty and they said it did not cover this part.

ENGINE

Had the car since 2021. Recently started shaking while driving over 45 mph. Took the car in gmc dealership where they told me it’s an engine issue and need a brand new engine. How would I need an engine having the car for 4 years? And there is no recall?

POWER TRAIN

July of 2023, lifters failed on left side of engine. Lifters replaced and cam shaft replaced. January 2025, lifters failed on right side of engine. Replaced. March 2025. Engine seized on interstate. Truck lost all power while driving, no warning signs prior. Dealership has no rental vehicles and we are not old enough to rent from a third party company so family had to drive 9 hours to our location so we wouldn’t be stranded. Three times this truck has failed us. GM is putting in a new motor as it’s still under warranty, but the new motor has no additional warranty. So basically this new motor will be warrantied for less than 7k miles. They cannot say if the new motor has the remanufactured lifters or not. So we could be facing the same exact issues. Can’t ever get ahold of anyone directly though GM.

ENGINE

July of 2023, lifters failed on left side of engine. Lifters replaced and cam shaft replaced. January 2025, lifters failed on right side of engine. Replaced. March 2025. Engine seized on interstate. Truck lost all power while driving, no warning signs prior. Dealership has no rental vehicles and we are not old enough to rent from a third party company so family had to drive 9 hours to our location so we wouldn’t be stranded. Three times this truck has failed us. GM is putting in a new motor as it’s still under warranty, but the new motor has no additional warranty. So basically this new motor will be warrantied for less than 7k miles. They cannot say if the new motor has the remanufactured lifters or not. So we could be facing the same exact issues. Can’t ever get ahold of anyone directly though GM.

ENGINE

Transmission recall was performed at a gmc dealership. Vehicle has been the the shop repeatedly since. Coolant control valve crank case position sensor new catalytic converter and dpf system. New low temp coolant loop pump. In the shop now for another low temp coolant pump that’s been shorted out. Seems to have on going electrical issues since recall was performed

ELECTRICAL SYSTEM

Transmission recall was performed at a gmc dealership. Vehicle has been the the shop repeatedly since. Coolant control valve crank case position sensor new catalytic converter and dpf system. New low temp coolant loop pump. In the shop now for another low temp coolant pump that’s been shorted out. Seems to have on going electrical issues since recall was performed

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 70 MPH, several unknown warning lights illuminated, with the message to shift to neutral displayed. The contact pulled over to the right side of the road and attempted to restart the vehicle; however, the vehicle failed to respond as needed. An unknown dealer was contacted. The contact stated that the failure had occurred on several occasions. The vehicle was towed to the dealer, where it was diagnosed that the engine was damaged and needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and offered a monetary payment. The approximate failure mileage was 80,000.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, there was an abnormal sound coming from the engine compartment. The contact pulled over to the side of the road and discovered that the engine oil level was low. The check engine warning light was illuminated. The failure occurred on several different occasions. The vehicle was taken to a dealer, where it was diagnosed that the lifters needed to be replaced. The vehicle was repaired; however, the failure persisted. The vehicle was taken to a different dealer (Legacy Westbank Buick GMC; 3611 Lapalco Blvd, Harvey, LA 70058) to be diagnosed. The vehicle was not diagnosed or repaired. The contact was taken to a different dealer (Mossy of Picayune; 241 Frontage Rd, Picayune, MS 39466) where it was diagnosed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 27,000.

ELECTRICAL SYSTEM

ESC ERROR PARKING BREAK NOT RELEASING Dashboard lights started flashing Check engine light came on

SERVICE BRAKES

ESC ERROR PARKING BREAK NOT RELEASING Dashboard lights started flashing Check engine light came on

ENGINE

Driving 75mph towing a 24' trailer and the motor just shut down and almost caused a massive pile up on [XXX] . INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

at 16,000 miles Bank 1 lifters fail and replaced under warranty. now at 90190 miles Bank 1 lifters have failed again this time damaging the camshaft. I have all the service records for this engine and I was verbally assured by GM in 2021 that they would cover this repair until 100,000 miles. I know from looking on Google and talking with service advisors at GM that the 6.2L ecoTec3 V8 engines are having multiple problems related to my issue. GM should be able to warranty this engine to 100,000 miles and from past experience this engine should last 200,000 with good service.

ELECTRICAL SYSTEM

This truck, along with many others, has had wiring harness issues. My truck has fought this issue within the first six months of owning the truck. Since Jan 2025 it has left me stranded 3 times to be towed, and in the shop a total of 6 times for wiring harness issues. Rubbing that GM is 100% aware of how its designed. This has caused the truck to hesitate, shake, lunge, go in and out of gear severely hard then shut off while driving. All three time this happened to me recently i was on the interstate. GM has work orders out with all the codes and symptoms but wont do anything about it. Yes, i am out of warranty, but i am now paying over $5,000 for a new harness to be installed by a different dealer. The dealer that had always worked on this truck requested $8,100 so i called a new GM shop. This is a large issue and they keep turning their back and not addressing the issue and putting drivers at risk! Can provide last diagnostics and can request all notes from Stoops Buick GMC in Muncie Indiana, i have a rather large file there on this truck.

UNKNOWN OR OTHER

My tailgate will randomly open on its own. I’ve had several instances( 5 or 6 times so far) when I’ve had open on its own. Only once so far when i was driving. Luckily, i was on my private road without anything in my bed that could fall out. I often carry mountain bikes over the tailgate which could pose a serious danger if the tailgate were to open when driving. Also earlier this evening when the tailgate came down on its own while driving, when I got to my destination, I was unable to open the tailgate at all from outside the vehicle. It is apparent the button to release the switch is malfunctioning. I was able to get it to open by using release button inside the vehicle.

ENGINE

Engine failure. Engine Locked up and truck shut down in the middle of the Freeway. Barely made it to the side of the road.

ENGINE

Driving on highway at approximately 70 mph and the engine completely cut off without warning. Error message on dash said put car in neutral and press the start button. After safely pulling over, the vehicle was never able to start or even crank. Towed back to the dealership. Catastrophic engine failure according to the dealership. Vehicle has the 6.2 V8 engine with known issues by GMC apparently. Only 32k miles and under warranty but dealership reports that replacement engines are on back order and they have not been able to source one.

ENGINE

Lifter failure resulting in damage cam shafts

POWER TRAIN

Transmission will slam hard then truck goes into low power mode and doesn’t shift.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated while the vehicle was parked, the contact attempted to turn off the vehicle; however, the vehicle remained running. A message was displayed to shift to park(P). The contact stated that the lights, radio, and other functions remained operational. On another occasion, the vehicle jerked, and the steering was difficult to turn. The dealer was contacted; however, the vehicle had not been taken to be diagnosed or repaired. The contact also stated that the trunk failed to fully close. The message that the trunk was open was displayed. The contact attempted to close the trunk and message on the displayed was turned off; however, the trunk remained slightly open. The vehicle was not taken to be diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 63,315.

ELECTRICAL SYSTEM

The contact owns a 2021 GMC Sierra 1500. The contact stated while the vehicle was parked, the contact attempted to turn off the vehicle; however, the vehicle remained running. A message was displayed to shift to park(P). The contact stated that the lights, radio, and other functions remained operational. On another occasion, the vehicle jerked, and the steering was difficult to turn. The dealer was contacted; however, the vehicle had not been taken to be diagnosed or repaired. The contact also stated that the trunk failed to fully close. The message that the trunk was open was displayed. The contact attempted to close the trunk and message on the displayed was turned off; however, the trunk remained slightly open. The vehicle was not taken to be diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 63,315.

LATCHES/LOCKS/LINKAGES:TRUNK LID:LATCH

The contact owns a 2021 GMC Sierra 1500. The contact stated while the vehicle was parked, the contact attempted to turn off the vehicle; however, the vehicle remained running. A message was displayed to shift to park(P). The contact stated that the lights, radio, and other functions remained operational. On another occasion, the vehicle jerked, and the steering was difficult to turn. The dealer was contacted; however, the vehicle had not been taken to be diagnosed or repaired. The contact also stated that the trunk failed to fully close. The message that the trunk was open was displayed. The contact attempted to close the trunk and message on the displayed was turned off; however, the trunk remained slightly open. The vehicle was not taken to be diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 63,315.

ENGINE

At cold start-up, engine (6.2) makes a metal-to-metal grinding sound for 60-90 seconds. After warm-up, a steady tick on the right side of the engine while running. I contacted GM and they said, " this was normal at start up". however, with me being a mechanical engineer, all of my school and working experience tells me anything grinding metal to metal is not good.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at 50 MPH, the transmission independently downshifted and the rear wheels seized. The contact stated that the rear wheels skidded. In addition, the contact noticed an abnormal clunking sound. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The dealer was made aware of the failure. The contact stated that the failure occurred immediately after the recall repair under NHTSA Campaign Number: 24V797000 (Power Train) was performed by the dealer. The manufacturer was not made aware of the failure. The failure mileage was unknown.

POWER TRAIN

P1098 coolant Control Valve malfunction and out of stock

ENGINE

Engine seized and now we need a new motor

POWER TRAIN

I own a 2021 GMC Sierra 1500 Duramax diesel. At around 60,000 miles, I received an engine coolant system alert through OnStar and retrieved a P1098 trouble code, which indicates a failure in the coolant control valve. This issue causes the engine fan to run excessively, creating loud noise, reduced fuel economy, and possible drivability concerns. After researching owner forums and talking to multiple service departments, I discovered this is a widespread problem among 2020–2022 GMC/Chevrolet Duramax 3.0L diesel owners. In many cases, the coolant control valve is failing prematurely, and the replacement part is on national backorder, suggesting a high failure rate. GM has not issued a recall or service bulletin to address the issue, and many customers are being told to pay out of pocket despite the systemic nature of the failure. This component is tied to engine temperature control, and failure could pose a safety risk if the engine overheats or derates unexpectedly. I am filing this complaint to document the issue and request NHTSA investigate this as a potential defect.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 30 MPH, there was an abnormal knocking sound coming from the engine compartment, after which the vehicle lost motive power. The contact was able to pull over to the side of the road. No warning lights were illuminated. The vehicle was taken to a dealer, who determined that the engine needed to be replaced. The vehicle was repaired. The contact stated that prior to the engine failure, the transmission was replaced. The manufacturer was not notified of the failure. The failure mileage was approximately 20,000.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 30 MPH, there was an abnormal knocking sound coming from the engine compartment, after which the vehicle lost motive power. The contact was able to pull over to the side of the road. No warning lights were illuminated. The vehicle was taken to a dealer, who determined that the engine needed to be replaced. The vehicle was repaired. The contact stated that prior to the engine failure, the transmission was replaced. The manufacturer was not notified of the failure. The failure mileage was approximately 20,000.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 24V797000 (Power Train); however, the dealer was unable to complete the recall and returned the vehicle to the contact in a worse condition than when the contact had dropped the vehicle off at the dealer. The contact stated that while attempting to drive the vehicle off the dealer parking lot, the check engine and reduced power warning lights flashed on the instrument cluster. The contact stated that he returned the vehicle to the dealer and was informed that the vehicle could not be repaired. The manufacturer was not made aware of the issue. The failure mileage was approximately 114,000.

ENGINE

My truck was part of a GM buyback program where GM Corporation bought the truck back to fix it around Aug 7th 2023 for engine problems. I am reporting this because I do not believe that GM ever reported this to NTSHA. There are also other issues happening at the same time period that should be looked into that may or may not be coincidences. At or before 10,126 miles the truck started having engine lifter and other engine issues. General Motors will not tell me exactly what was done other than lifters according to paperwork supplied. It may have had other issues like a spun bearing but it was never disclosed. Can NTSHA please look into this and information is found, could I please get the records. I asked for the paperwork of what was done while GM owned and troubleshot all the problems. I was told that information is only available to the original owner and I could not have it. It is very frustrating when General Motors Corporate use owner’s personal data as a way to hide what was done and not have to disclose required information. I am asking for service records while General Motors owned it and the service records they did to fix it. I know that there are many more engine problems that are not documented on the vehicle summary. GM will not buy back the truck over a few lifter issues. The truck was later fixed and Art Gamblin Motorsv in Enumclaw Wa, purchased it. I am told it is fixed but have no real paperwork proving this, I was able to purchase an extended warranty just in case. There is also quite a few of battery and electronic issues that do not seem normal with the car as well. The battery was replaced at 10,126 miles at the same time as the engine issues and the battery module was replaced at 29,536 miles. At 29,875 miles and 29,965 some type of communications module and On Star module was replaced. This is the around the same time as the truck was having engine issues and was eventually bought back for what is called “engine noise”.

ELECTRICAL SYSTEM

My truck was part of a GM buyback program where GM Corporation bought the truck back to fix it around Aug 7th 2023 for engine problems. I am reporting this because I do not believe that GM ever reported this to NTSHA. There are also other issues happening at the same time period that should be looked into that may or may not be coincidences. At or before 10,126 miles the truck started having engine lifter and other engine issues. General Motors will not tell me exactly what was done other than lifters according to paperwork supplied. It may have had other issues like a spun bearing but it was never disclosed. Can NTSHA please look into this and information is found, could I please get the records. I asked for the paperwork of what was done while GM owned and troubleshot all the problems. I was told that information is only available to the original owner and I could not have it. It is very frustrating when General Motors Corporate use owner’s personal data as a way to hide what was done and not have to disclose required information. I am asking for service records while General Motors owned it and the service records they did to fix it. I know that there are many more engine problems that are not documented on the vehicle summary. GM will not buy back the truck over a few lifter issues. The truck was later fixed and Art Gamblin Motorsv in Enumclaw Wa, purchased it. I am told it is fixed but have no real paperwork proving this, I was able to purchase an extended warranty just in case. There is also quite a few of battery and electronic issues that do not seem normal with the car as well. The battery was replaced at 10,126 miles at the same time as the engine issues and the battery module was replaced at 29,536 miles. At 29,875 miles and 29,965 some type of communications module and On Star module was replaced. This is the around the same time as the truck was having engine issues and was eventually bought back for what is called “engine noise”.

POWER TRAIN

Truck started to lose power or slip on quick acceleration on highway Truck would jolt or shudder. 63000 miles. Dealer diagnosed truck needs Torque converter and a valve body replacement. No warning lights Contacted GM. Have a case number, was told to take to dealer. It’s at dealer now, getting repaired. I’m wondering if GM has a bigger problem with transmission recall

ELECTRICAL SYSTEM:WIRING:FUSES AND CIRCUIT BREAKERS

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 60 MPH, there was an abnormal knocking sound coming from the engine compartment, after which the vehicle lost motive power. The contact was able to pull over to the shoulder of the roadway, where the vehicle failed to restart. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic, who determined that the engine had seized. The contact was also informed that the fuse box needed to be replaced. The vehicle was repaired, but the failure reoccurred. After investigating the failure, the contact related the failure to NHTSA Action Number: PE25001 (Engine, Engine and Engine Cooling). The manufacturer was not notified of the failure. The failure mileage was 63,000.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 60 MPH, there was an abnormal knocking sound coming from the engine compartment, after which the vehicle lost motive power. The contact was able to pull over to the shoulder of the roadway, where the vehicle failed to restart. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic, who determined that the engine had seized. The contact was also informed that the fuse box needed to be replaced. The vehicle was repaired, but the failure reoccurred. After investigating the failure, the contact related the failure to NHTSA Action Number: PE25001 (Engine, Engine and Engine Cooling). The manufacturer was not notified of the failure. The failure mileage was 63,000.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 60 MPH, there was an abnormal knocking sound coming from the engine compartment, after which the vehicle lost motive power. The contact was able to pull over to the shoulder of the roadway, where the vehicle failed to restart. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic, who determined that the engine had seized. The contact was also informed that the fuse box needed to be replaced. The vehicle was repaired, but the failure reoccurred. After investigating the failure, the contact related the failure to NHTSA Action Number: PE25001 (Engine, Engine and Engine Cooling). The manufacturer was not notified of the failure. The failure mileage was 63,000.

POWER TRAIN

After 2 years of owning the vehicle, after every oil change, it would indicate low oil just before an oil change causing for us to add an additional a quart of oil to keep it running smoothly. We informed the service technician of the situation on multiple occasions and no further inspection was completed, and just an oil change was serviced. After a few months we noticed the engine was running rough and a white smoke coming out of the exhaust on acceleration then the check engine light came on. We brought the car to get tires replaced and to service the check engine light, the technician stated that the check engine light a failure in the catalytic converter. We brought the vehicle to the local GMC service center, where they indicated that the we required a replacement engine because of catastrophic engine failure. We reported that the check engine light was due to catalytic converter failure. The service technician ensured that the priority was the replacement of the full engine not indicating what was the main cause of engine failure stating that the catalytic converter could have led to the failure of the engine as well. We replaced the engine, and after 3 months of vehicle being in the shop the engine was replaced. Three days after receiving the vehicle, a check engine light came on. We did not drive the vehicle until we had to return it back to the service center. The service technician stated that it is due to a lack of communication from the engine to the ECU. The technician called the following Monday stating that the check engine light was due the catalytic converter. We told the technician that was the primary reason that the customer the vehicle in the first place. We asked if there was an alternative to replacing the catalytic converter since we already paid 12k for the engine replacement. We asked if they had taken apart the catalytic converter to confirm its not a sensor issue. They replied that the codes indicates its the whole converter.

ENGINE

After 2 years of owning the vehicle, after every oil change, it would indicate low oil just before an oil change causing for us to add an additional a quart of oil to keep it running smoothly. We informed the service technician of the situation on multiple occasions and no further inspection was completed, and just an oil change was serviced. After a few months we noticed the engine was running rough and a white smoke coming out of the exhaust on acceleration then the check engine light came on. We brought the car to get tires replaced and to service the check engine light, the technician stated that the check engine light a failure in the catalytic converter. We brought the vehicle to the local GMC service center, where they indicated that the we required a replacement engine because of catastrophic engine failure. We reported that the check engine light was due to catalytic converter failure. The service technician ensured that the priority was the replacement of the full engine not indicating what was the main cause of engine failure stating that the catalytic converter could have led to the failure of the engine as well. We replaced the engine, and after 3 months of vehicle being in the shop the engine was replaced. Three days after receiving the vehicle, a check engine light came on. We did not drive the vehicle until we had to return it back to the service center. The service technician stated that it is due to a lack of communication from the engine to the ECU. The technician called the following Monday stating that the check engine light was due the catalytic converter. We told the technician that was the primary reason that the customer the vehicle in the first place. We asked if there was an alternative to replacing the catalytic converter since we already paid 12k for the engine replacement. We asked if they had taken apart the catalytic converter to confirm its not a sensor issue. They replied that the codes indicates its the whole converter.

POWER TRAIN

See attached document for complaint.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving approximately 75 MPH, the rear wheels locked up. The failure had occurred on several occasions. The contact stated that several unknown warning lights were illuminated. The vehicle was towed to a dealer where it was diagnosed and determined that a software update was needed. The vehicle was repaired under an NHTSA Campaign Number: 24V797000 (Power Train); however, the failure persisted. The manufacturer was not notified of the failure. The failure mileage was approximately 35,000.

ELECTRICAL SYSTEM

Multi functional tail gate will open on its own while driving. I have had this repaired by gm 3 times and still have issues. This problem is currently on the recall list for 2500 hd series trucks and the 1500 series trucks in Canada but not on recall in united states. This problem poses a life threatening problem while on the road due to contents of truck possible becoming projectiles to other drivers due to tailgate opening on its own .

AIR BAGS

Airbag system did not deploy but smoke in cabin during a crash. Video of front, rear and inside cabin shows the rear end passenger side impact at an estimated 45-50 MPH. I saw smoke in cabin, disturbed with anxiety after crash waiting for bags to deploy accidentally. The airbag deployed red light illuminated notifying an airbag deployment. I received a GM message through the vehicle report application stating that my airbag system malfunctioned and I needed to take the vehicle to a service department for repair as soon as possible. This crash was a total loss of the GMC Sierra, this was how hard the vehicle was hit. Why did the airbag system smoke? Why did the airbags not deploy? Why did I receive a Malfunctioning Airbag system message from GMC? Video shows that if the airbag system would have deployed on the steering wheel I would have had less head and neck trauma when whipping backward and then forward.

POWER TRAIN

[XXX], I PURCHASED A 2021 GMC SIERRA 1500 FROM FAULKNER CHEVROLET IN BETHLEHEM, PA. I TEST DROVE THE VEHICLE BEFORE PURCHASE AND IT SHOWED NO INDICATION OF ANY MECHANICAL ISSUES THAT I WAS ABLE TO DETECT. I WAS SHOWN BY THE DEALERSHIP THE CARFAX AND WAS INFORMED THAT THERE ARE CURRENTLY NO RECALLS FOR THE VEHICLE. I WAS LED TO BELIEVE THAT THE VEHICLE WAS IN GOOD CONDITION AND SAFE TO DRIVE AND, THEREFORE, AGREED TO PURCHASE THE VEHICLE FOR THE AFOREMENTIONED PRICE (INCLUDING TAX AND TITLE FEES). I PURCHASED THE VEHICLE WITH 60,077 MILES ON IT, AND AFTER DRIVING IT NORMALLY FOR ONLY 5 DAYS (ON [XXX]) IT BROKE DOWN AND I WAS STRANDED ON THE HIGHWAY 16 HOURS FROM HOME. I WAS ABLE TO GET THE VEHICLE TOWED AND PAID $1,200 FOR THE STARTER TO BE REPLACED, WHICH IS WHAT THE MECHANIC SUGGESTED BUT THIS ENDED UP BEING ENTIRELY UNNECESSARY AS THE REAL ISSUE WAS DUE TO A CATASTROPHIC DEFECT IN THE ENGINE. AFTER THE STARTER WAS REPLACED, I WAS DRIVING THE VEHICLE ONLY A FEW DAYS LATER (ON [XXX]) AND IT SUFFERED A CATASTROPHIC ENGINE FAILURE WHILE DRIVING 70MPH ON THE HIGHWAY. I LOST CONTROL OF THE VEHICLE AND NEARLY GOT IN A COLLISION WITH ANOTHER VEHICLE. I WAS ABLE TO GET THE VEHICLE TO THE NEAREST AUTO SHOP AND AFTER INSPECTING THE VEHICLE THEY INFORMED ME THAT THERE IS A SERIOUS ENGINE ISSUE RELATING TO A SEIZED BEARING AND THE ENGINE WILL NEED TO BE REBUILT ENTIRELY. AT THIS POINT IT HAD BEEN ONLY 12 DAYS SINCE THE PURCHASE AND THE ODEMETER READ 61,662 (1,585 MILES DRIVEN SINCE PURCHASE). DUE TO THE FAULTY VEHICLE, I WAS FORCED TO PAY TO HAVE THE VEHICLE SHIPPED FROM THE LOCATION WHERE IT BROKE DOWN TO THE DEALERSHIP WHERE I ORIGINALLY BOUGHT IT (AROUND $1,200). FAULKNER CHEVROLET KNOWINGLY SOLD ME AN UNSAFE VEHICLE THAT THEY WERE WELL AWARE HAD A DEFECTIVE 6.2L V8 ENGINE. THIS DEFECT IS CURRENTLY UNDER INVESTIGATION BY THE NHTSA AND FAULKNER CHEVROLET PURPOSEFULLY OMMITTED THIS CRUCIAL INFORMATION UNTIL AFTER THE VEHICLE WAS SOLD. CLEARLY, THIS IS AN UNETHICAL BUS INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORM

ENGINE

[XXX], I PURCHASED A 2021 GMC SIERRA 1500 FROM FAULKNER CHEVROLET IN BETHLEHEM, PA. I TEST DROVE THE VEHICLE BEFORE PURCHASE AND IT SHOWED NO INDICATION OF ANY MECHANICAL ISSUES THAT I WAS ABLE TO DETECT. I WAS SHOWN BY THE DEALERSHIP THE CARFAX AND WAS INFORMED THAT THERE ARE CURRENTLY NO RECALLS FOR THE VEHICLE. I WAS LED TO BELIEVE THAT THE VEHICLE WAS IN GOOD CONDITION AND SAFE TO DRIVE AND, THEREFORE, AGREED TO PURCHASE THE VEHICLE FOR THE AFOREMENTIONED PRICE (INCLUDING TAX AND TITLE FEES). I PURCHASED THE VEHICLE WITH 60,077 MILES ON IT, AND AFTER DRIVING IT NORMALLY FOR ONLY 5 DAYS (ON [XXX]) IT BROKE DOWN AND I WAS STRANDED ON THE HIGHWAY 16 HOURS FROM HOME. I WAS ABLE TO GET THE VEHICLE TOWED AND PAID $1,200 FOR THE STARTER TO BE REPLACED, WHICH IS WHAT THE MECHANIC SUGGESTED BUT THIS ENDED UP BEING ENTIRELY UNNECESSARY AS THE REAL ISSUE WAS DUE TO A CATASTROPHIC DEFECT IN THE ENGINE. AFTER THE STARTER WAS REPLACED, I WAS DRIVING THE VEHICLE ONLY A FEW DAYS LATER (ON [XXX]) AND IT SUFFERED A CATASTROPHIC ENGINE FAILURE WHILE DRIVING 70MPH ON THE HIGHWAY. I LOST CONTROL OF THE VEHICLE AND NEARLY GOT IN A COLLISION WITH ANOTHER VEHICLE. I WAS ABLE TO GET THE VEHICLE TO THE NEAREST AUTO SHOP AND AFTER INSPECTING THE VEHICLE THEY INFORMED ME THAT THERE IS A SERIOUS ENGINE ISSUE RELATING TO A SEIZED BEARING AND THE ENGINE WILL NEED TO BE REBUILT ENTIRELY. AT THIS POINT IT HAD BEEN ONLY 12 DAYS SINCE THE PURCHASE AND THE ODEMETER READ 61,662 (1,585 MILES DRIVEN SINCE PURCHASE). DUE TO THE FAULTY VEHICLE, I WAS FORCED TO PAY TO HAVE THE VEHICLE SHIPPED FROM THE LOCATION WHERE IT BROKE DOWN TO THE DEALERSHIP WHERE I ORIGINALLY BOUGHT IT (AROUND $1,200). FAULKNER CHEVROLET KNOWINGLY SOLD ME AN UNSAFE VEHICLE THAT THEY WERE WELL AWARE HAD A DEFECTIVE 6.2L V8 ENGINE. THIS DEFECT IS CURRENTLY UNDER INVESTIGATION BY THE NHTSA AND FAULKNER CHEVROLET PURPOSEFULLY OMMITTED THIS CRUCIAL INFORMATION UNTIL AFTER THE VEHICLE WAS SOLD. CLEARLY, THIS IS AN UNETHICAL BUS INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORM

ELECTRICAL SYSTEM

[XXX], I PURCHASED A 2021 GMC SIERRA 1500 FROM FAULKNER CHEVROLET IN BETHLEHEM, PA. I TEST DROVE THE VEHICLE BEFORE PURCHASE AND IT SHOWED NO INDICATION OF ANY MECHANICAL ISSUES THAT I WAS ABLE TO DETECT. I WAS SHOWN BY THE DEALERSHIP THE CARFAX AND WAS INFORMED THAT THERE ARE CURRENTLY NO RECALLS FOR THE VEHICLE. I WAS LED TO BELIEVE THAT THE VEHICLE WAS IN GOOD CONDITION AND SAFE TO DRIVE AND, THEREFORE, AGREED TO PURCHASE THE VEHICLE FOR THE AFOREMENTIONED PRICE (INCLUDING TAX AND TITLE FEES). I PURCHASED THE VEHICLE WITH 60,077 MILES ON IT, AND AFTER DRIVING IT NORMALLY FOR ONLY 5 DAYS (ON [XXX]) IT BROKE DOWN AND I WAS STRANDED ON THE HIGHWAY 16 HOURS FROM HOME. I WAS ABLE TO GET THE VEHICLE TOWED AND PAID $1,200 FOR THE STARTER TO BE REPLACED, WHICH IS WHAT THE MECHANIC SUGGESTED BUT THIS ENDED UP BEING ENTIRELY UNNECESSARY AS THE REAL ISSUE WAS DUE TO A CATASTROPHIC DEFECT IN THE ENGINE. AFTER THE STARTER WAS REPLACED, I WAS DRIVING THE VEHICLE ONLY A FEW DAYS LATER (ON [XXX]) AND IT SUFFERED A CATASTROPHIC ENGINE FAILURE WHILE DRIVING 70MPH ON THE HIGHWAY. I LOST CONTROL OF THE VEHICLE AND NEARLY GOT IN A COLLISION WITH ANOTHER VEHICLE. I WAS ABLE TO GET THE VEHICLE TO THE NEAREST AUTO SHOP AND AFTER INSPECTING THE VEHICLE THEY INFORMED ME THAT THERE IS A SERIOUS ENGINE ISSUE RELATING TO A SEIZED BEARING AND THE ENGINE WILL NEED TO BE REBUILT ENTIRELY. AT THIS POINT IT HAD BEEN ONLY 12 DAYS SINCE THE PURCHASE AND THE ODEMETER READ 61,662 (1,585 MILES DRIVEN SINCE PURCHASE). DUE TO THE FAULTY VEHICLE, I WAS FORCED TO PAY TO HAVE THE VEHICLE SHIPPED FROM THE LOCATION WHERE IT BROKE DOWN TO THE DEALERSHIP WHERE I ORIGINALLY BOUGHT IT (AROUND $1,200). FAULKNER CHEVROLET KNOWINGLY SOLD ME AN UNSAFE VEHICLE THAT THEY WERE WELL AWARE HAD A DEFECTIVE 6.2L V8 ENGINE. THIS DEFECT IS CURRENTLY UNDER INVESTIGATION BY THE NHTSA AND FAULKNER CHEVROLET PURPOSEFULLY OMMITTED THIS CRUCIAL INFORMATION UNTIL AFTER THE VEHICLE WAS SOLD. CLEARLY, THIS IS AN UNETHICAL BUS INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORM

ENGINE

I was driving 50mph when my check engine light started flashing. The engine had very little power and there was a new consistent engine knock. I took to GMC dealership and they informed me that half of the engine lifters failed and a pushrod was bent. There was no warning prior to the incident. I have had the vehicle serviced only at the dealership and have only used premium fuel. The truck has 88,000 miles.

ENGINE

I've now had 2 engines fail catastrophically, One at 19,191 miles and the second failure at 80,661. Both are the 6.2L engine. The first had crank bearings that were black. The second I was not informed of the cause but that it was seized leaving me stranded on the roadside.

ENGINE

Engine failed and had to be replaced. GMC was absolutely no help had to bring to local gas station where i had to pay almost $12,000 to get it fixed. The truck has been in shop frequently for oil issues with this motor but GMC just jerks you around. I am in sales and need my vehicle to support my family

ENGINE

While driving the vehicle shut off in the middle of the roadway. It sat in the road till it got towed. Brought it to the dealership where it was purchased and they said the engine was blown. Themis vehicle is equipped with the 6.2 motor. It happened February 16th. The dealership confirmed the engine failed. It is siting currently at the dealership and could be available for inspection.

ENGINE

AFM lifters failed which caused cam shaft to collapse under 35k miles. Had to remove while front end to repair

ENGINE

Subject: Complaint Regarding Recurring Engine Failure in 2021 GMC Sierra AT4 Dear National Highway Traffic Safety Administration, I am writing to formally express my concern regarding recurring engine failures in my 2021 GMC Sierra AT4 (6.2L engine). At 23,000 miles, the vehicle suffered a complete breakdown due to failure of cylinder #8, lifters, and push rods. General Motors covered the repairs at that time. However, at 97,000 miles, the exact same issue reoccurred, resulting in significant engine damage. The dealership diagnosed a misfire in cylinder #8, leading to the removal of the right cylinder head, where they found a bent push rod, spun lifter, damaged camshaft lobe, and lifter roller. The repair estimate totals $9,746, but GM has refused to cover the costs, despite us having an extended warranty purchased from the dealership. This recurring failure raises serious concerns about engine reliability and manufacturing defects in General Motors vehicles. I urge the NHTSA to investigate this issue, as multiple GMC and Chevrolet owners have reported similar problems with the 6.2L engine lifter and camshaft system. This is not just a costly repair but a potential safety hazard that GM has failed to properly address. Thank you for your attention to this matter. I appreciate any guidance or action the NHTSA can take to hold GM accountable and ensure consumer protection.

POWER TRAIN

Subject: Complaint Regarding Recurring Engine Failure in 2021 GMC Sierra AT4 Dear National Highway Traffic Safety Administration, I am writing to formally express my concern regarding recurring engine failures in my 2021 GMC Sierra AT4 (6.2L engine). At 23,000 miles, the vehicle suffered a complete breakdown due to failure of cylinder #8, lifters, and push rods. General Motors covered the repairs at that time. However, at 97,000 miles, the exact same issue reoccurred, resulting in significant engine damage. The dealership diagnosed a misfire in cylinder #8, leading to the removal of the right cylinder head, where they found a bent push rod, spun lifter, damaged camshaft lobe, and lifter roller. The repair estimate totals $9,746, but GM has refused to cover the costs, despite us having an extended warranty purchased from the dealership. This recurring failure raises serious concerns about engine reliability and manufacturing defects in General Motors vehicles. I urge the NHTSA to investigate this issue, as multiple GMC and Chevrolet owners have reported similar problems with the 6.2L engine lifter and camshaft system. This is not just a costly repair but a potential safety hazard that GM has failed to properly address. Thank you for your attention to this matter. I appreciate any guidance or action the NHTSA can take to hold GM accountable and ensure consumer protection.

LATCHES/LOCKS/LINKAGES

The contact owns a 2021 GMC Sierra 1500. The contact stated that the tailgate opened unintendedly while driving, and while the vehicle was parked. The contact stated that the failure had been recurring. The vehicle was taken to the dealer but was not diagnosed or repaired. The contact related the failure to GM Campaign Number: N232426400. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 76,000.

ENGINE

My Vehicle went into the dealer on January 21, 2025. My initial complaint was tapping noise, I was advised that my vehicle had collapse lifters issue several days later I was informed that they have found metal shards in the lower end and found a bad crank bearing and crank. I was told that the vehicle will need an engine replacement, and that the engine is on back order with no date of fulfilment. My vehicle has 66,700 miles I was advised was out of warranty and that GM will only cover half of the estimated cost of 11,000.00.

VISIBILITY/WIPER

Wipers work intermittently

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at approximately 80 MPH, the vehicle stalled and failed to return to normal operation. No warning light was illuminated. The vehicle was towed to be diagnosed. The contact was informed that the rod bearings needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 134,000.

ELECTRICAL SYSTEM

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, the transmission slammed into gear and the rear wheels locked up. In addition, the vehicle decelerated independently. The vehicle was driven to the shoulder of the road and turned off. The vehicle was restarted, and the contact noticed that the vehicle was independently reset. The vehicle was taken to the dealer where it was diagnosed with a failed wiring harness. The contact was informed that the wiring harness needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was filed. The contact was advised to contact the NHTSA Hotline and report the failure. The failure mileage was approximately 60,129.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 55 MPH, the vehicle started making a knocking sound. There were no warning lights illuminated. The contact picked up his son from school and drove the vehicle to the dealer. The contact stated that while depressing the accelerator pedal, the knocking sound became louder, and the vehicle was losing motive power. The vehicle was taken to a dealer and diagnosed with engine failure. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 58,522.

ENGINE

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 55 MPH, the vehicle started making a knocking sound. There were no warning lights illuminated. The contact picked up his son from school and drove the vehicle to the dealer. The contact stated that while depressing the accelerator pedal, the knocking sound became louder, and the vehicle was losing motive power. The vehicle was taken to a dealer and diagnosed with engine failure. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 58,522.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at various speeds up an incline, the vehicle was vibrating and shuddering. The failure persisted over time. There were no warning lights illuminated. The vehicle was taken to the local dealer, but the vehicle was not diagnosed or repaired. The vehicle was taken to a transmission shop, and it was determined that the transmission needed to be replaced. The manufacturer was not contacted. The approximate failure mileage was 68,000.

ENGINE

While driving on the highway the engine 6.2 GM seized suddenly at high speed. The truck shut off completely and left rolling without any control. I had work my way accross lanes to the breakdown lane. While doing so I was almost hit by an 18 wheel trailer truck, who luckily was able to change lanes to avoid hitting me. The reason I was almost hit was because of my low speed since I had now power or acceleration.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at various speeds and depressing the accelerator pedal, the vehicle hesitated to respond and shuddered. The vehicle was taken to the dealer, where the fuel tank was cleaned, and the contact added fuel treatment to the fuel, as recommended by the dealer; however, the failure recurred. The contact stated that while driving from a complete stop, uphill, and while driving 50 MPH, the vehicle shuddered and experienced erratic transmission shifting. The check engine warning light was illuminated. The vehicle was taken to Dixie Buick GMC (14565 S Tamiami Trl, Fort Myers, FL 33912); where it was determined that the vehicle was experiencing a abnormal shudder. The dealer replaced the transmission fluid; however, the failure persisted. The contact stated that the failure had become progressively worse and mostly occurred at 1,200 RPM. The dealer was contacted, and an appointment was scheduled for diagnostic testing. The vehicle was not diagnosed or repaired. The contact related the failure to NHTSA Campaign Number: 24V797000 (Power Train); however, the VIN was not included. The manufacturer was notified of the failure. The failure mileage was approximately 8,000.

ENGINE

I purchased a new 2021 GMC Sierra Denali with a 6.2L engine on 03/05/2022. On November 10, 2022, I started the truck, and the engine seized up. The truck had 9018 miles on it and 274 engine hours. The main bearings and possibly the connecting rods bearings was the problem. On January 27, 2023, I finally got a new engine installed in my truck. I had to pay for the repairs.

ENGINE

Driver side lifters collapsed and push rods failed on freeway without warning at 12900 miles on truck.

ENGINE AND ENGINE COOLING

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, there was an abnormal clunking sound coming from the rear suspension. The check engine warning light was illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the rear suspension. The vehicle was repaired, but the failure reoccurred 4,000 miles later. The contact stated that while reversing, the contact heard an abnormal clunking sound coming from the rear suspension. The contact also stated that there was also a strong antifreeze odor permeating the interior of the vehicle. The vehicle was taken back to the dealer, but not yet diagnosed. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 38,000.

SUSPENSION

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, there was an abnormal clunking sound coming from the rear suspension. The check engine warning light was illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the rear suspension. The vehicle was repaired, but the failure reoccurred 4,000 miles later. The contact stated that while reversing, the contact heard an abnormal clunking sound coming from the rear suspension. The contact also stated that there was also a strong antifreeze odor permeating the interior of the vehicle. The vehicle was taken back to the dealer, but not yet diagnosed. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 38,000.

ENGINE

On the morning of 1/19/25, my 2021 GMC Sierra 6.2L AT4 went into limp mode heading south on HWY 207 in Leavenworth, WA at approximately 60 m.p.h. Fortunately, I was able to avoid a rear end collision. I quickly turned the truck off in the middle of the road and restarted it with a CEL. When I returned home almost 180 miles away, my local mechanic diagnosed a code P0303 and cleared it. Since, the truck has continued to shutter at various speeds without throwing a code. It is currently at Haselwood GMC in Bremerton, WA being scanned, recorded, and findings set to GM waiting for resolve. I have notes, exact dates, times, call records, return voice mail messages, and dealership personnel spoken to, etc. The dealer’s lead technician and I were able to replicate the shutter on a road test together on 1/27/25 at 3 p.m. after having driven just 10 miles. During my visit on the morning of 1/30/25, the lead technician stated he has since been able to replicate the shutter seemingly getting worse. I was strongly encouraged by the service manager, service writer, and lead technician their collective “personal recommendation” was to not take the truck back. Haselwood has had the truck since 1/27/25. Still awaiting a response and resolution.

VEHICLE SPEED CONTROL

On the morning of 1/19/25, my 2021 GMC Sierra 6.2L AT4 went into limp mode heading south on HWY 207 in Leavenworth, WA at approximately 60 m.p.h. Fortunately, I was able to avoid a rear end collision. I quickly turned the truck off in the middle of the road and restarted it with a CEL. When I returned home almost 180 miles away, my local mechanic diagnosed a code P0303 and cleared it. Since, the truck has continued to shutter at various speeds without throwing a code. It is currently at Haselwood GMC in Bremerton, WA being scanned, recorded, and findings set to GM waiting for resolve. I have notes, exact dates, times, call records, return voice mail messages, and dealership personnel spoken to, etc. The dealer’s lead technician and I were able to replicate the shutter on a road test together on 1/27/25 at 3 p.m. after having driven just 10 miles. During my visit on the morning of 1/30/25, the lead technician stated he has since been able to replicate the shutter seemingly getting worse. I was strongly encouraged by the service manager, service writer, and lead technician their collective “personal recommendation” was to not take the truck back. Haselwood has had the truck since 1/27/25. Still awaiting a response and resolution.

POWER TRAIN

On the morning of 1/19/25, my 2021 GMC Sierra 6.2L AT4 went into limp mode heading south on HWY 207 in Leavenworth, WA at approximately 60 m.p.h. Fortunately, I was able to avoid a rear end collision. I quickly turned the truck off in the middle of the road and restarted it with a CEL. When I returned home almost 180 miles away, my local mechanic diagnosed a code P0303 and cleared it. Since, the truck has continued to shutter at various speeds without throwing a code. It is currently at Haselwood GMC in Bremerton, WA being scanned, recorded, and findings set to GM waiting for resolve. I have notes, exact dates, times, call records, return voice mail messages, and dealership personnel spoken to, etc. The dealer’s lead technician and I were able to replicate the shutter on a road test together on 1/27/25 at 3 p.m. after having driven just 10 miles. During my visit on the morning of 1/30/25, the lead technician stated he has since been able to replicate the shutter seemingly getting worse. I was strongly encouraged by the service manager, service writer, and lead technician their collective “personal recommendation” was to not take the truck back. Haselwood has had the truck since 1/27/25. Still awaiting a response and resolution.

ENGINE

lifters in the left and right side snapped into 3 pieces. Caused engine failure happened 2 different times. All before 50,000 miles. The first time was before 30,000 miles.

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 24V797000 (Power Train); however, the contact believed that the remedy offered would cripple the vehicle and interfere with his work. The contact works in Alaska and the remedy involved the transmission being limited to fifth gear, preventing the possibility of a wheel lock up condition, which could occur while downshifting from eighth gear. The manufacturer was made aware of the issue and advised the contact to find a dealer that could repair the transmission. The contact had not experienced a failure. Parts distribution disconnect.

ENGINE

Engine failure

POWER TRAIN

The engine locked up with no warning I called the dealership and they said it was out of warranty as it has 77000 miles. upon further investigation I found that the front main bearing on the engine had gone bad and caused the engine to lock up. GMC refused to accept any responsibility for the failure.

ELECTRICAL SYSTEM

Assure Guard (877-831-3077) Contract number [XXX] GMC Customer Care Melissa (866-790-5600 Ext [XXX] ) Case#[XXX] Dealership: Phil Moore GMC (601-956-0150) My truck is barely 4 years old. I should not have this problem . Why is it no one guarantee the product they make? I paid too much money for this vehicle financing it as a new truck. I paid 766.95 to replace/install the shark fan antenna on the roof of my truck because it literally came loose on his own. No one (dealership, GMC, Assure Guard) would assist with repairs. The shark fin antenna started leaking water and it was wobbly where, it was no longer sealed on the body of the truck. Water leaking through out the ceiling/roof. I didn’t do anything to cause this! GMC Customer Care refused to refund nor, help with the cost of repair. I tried to file a claim with my extended warranty company(Assure Guard) contract number [XXX] - they refused to cover the antenna. I have owned several 1500 truck models, and none of them has had the antenna to fall off the vehicle. I had to return to Phil Moore, GMC a second time because they did not properly seal the antenna. This caused the whole interior of my truck to be drenched with rainwater. I am upset with the dealership, GMC and my extended warranty(Assure Guard) because I spent too much money on my vehicle to have this happen and I would like to be refunded. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

We have had several times where we are on highway and our truck like slams on the brakes causing us to lose control. It was a recall on it and GMC fixed it and within the same week of them fixing it it happened 3 times back to back. Making my truck to force another car to steer out of my way and actually went off the highway. Thank god it was just dirt snd he didn’t get hurt or anything. But I am scared to even drive my vehicle! It starting Happening for about a year now. And it would only do it like every couple months but now it’s has done it 6 times in the last 2 months!

FUEL/PROPULSION SYSTEM

We have had several times where we are on highway and our truck like slams on the brakes causing us to lose control. It was a recall on it and GMC fixed it and within the same week of them fixing it it happened 3 times back to back. Making my truck to force another car to steer out of my way and actually went off the highway. Thank god it was just dirt snd he didn’t get hurt or anything. But I am scared to even drive my vehicle! It starting Happening for about a year now. And it would only do it like every couple months but now it’s has done it 6 times in the last 2 months!

SERVICE BRAKES

We have had several times where we are on highway and our truck like slams on the brakes causing us to lose control. It was a recall on it and GMC fixed it and within the same week of them fixing it it happened 3 times back to back. Making my truck to force another car to steer out of my way and actually went off the highway. Thank god it was just dirt snd he didn’t get hurt or anything. But I am scared to even drive my vehicle! It starting Happening for about a year now. And it would only do it like every couple months but now it’s has done it 6 times in the last 2 months!

ENGINE

I was notified at the dealership that my truck had metal in the oil that is causing the oil sensor pump to send a ln engine code. The fix is a new engine.

UNKNOWN OR OTHER

Transmission, rear wheel lock up issue. Dealer performed recall notice work. Truck still has same issue after dealer visit. When issue starts, feels like you ran over something in the road, All warning lights are on, loss of power to engine and the engine did quit working once. Door locks continue to cycle repeatedly, multiple screen warnings appear on dashboard. It appears that everything that could go wrong happens at once. Have heard transmission valve control modules is a major problem with GM 10 speed transmissions.

ENGINE

Engine knocking and metal in oil. Been to the dealership and even though it's under warranty they will not act on it due to no check engine light present. It's making it difficult to trust driving the vehicle anymore because of the thought of the engine shutting down without warning anytime. This complaint is documented and confirmed by a dealership. They made me pay the check out fee and recommended i keep driving the vehicle until the motor locks up.

WHEELS

Le Moteur Le 13 décembre 2024 le véhicule arrêté subitement je tente de le redémarrer et ne demarre plus à plusieurs reprises je branche un obd2 et cela indique crank sensor j'envoie le véhicule au dealer et me dise qu'il y a quelque chose dans la base et aujourd'hui ils y est encore Les pneus Certains Flan de pneu de ce véhicule sont fissures tous le tour des roues

ENGINE

Le Moteur Le 13 décembre 2024 le véhicule arrêté subitement je tente de le redémarrer et ne demarre plus à plusieurs reprises je branche un obd2 et cela indique crank sensor j'envoie le véhicule au dealer et me dise qu'il y a quelque chose dans la base et aujourd'hui ils y est encore Les pneus Certains Flan de pneu de ce véhicule sont fissures tous le tour des roues

ENGINE

Lifter noises, error codes for misfires, lost power

POWER TRAIN

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at approximately 20 MPH, the vehicle lost motive power. The contact stated that the accelerator pedal was depressed; however, the vehicle failed to respond as needed. The contact moved the transmission lever from drive(D) to neutral(N) to reverse(R) several times and was able to drive back to the residence. The contact stated that the check engine warning light was illuminated. The contact had the vehicle towed to a local dealer. The dealer diagnosed the failure and determined that the transmission control valve had failed and needed to be replaced. The vehicle was repaired; however, the contact stated that the failure had reoccurred. The vehicle was taken back to the same dealer who advised that the transmission control valve had failed, but the parts needed to complete the repair were on back-order. The vehicle was not repaired. The contact had asked the dealer what the possibility of the same failure reoccurring after the second replacement of the control valve and the dealer advised that the valve would fail again. The vehicle was awaiting repair. The manufacturer was informed of the failure. The failure mileage was 27,676.

POWER TRAIN

The control valve system on my 2021 gmc has malfunctioned and this is the second time, currently sitting at Nelson GM Dealer in Fergus Falls MN. I have to drive back to TN as thats where I live and the mechanic said this issue will happen again. This vehicle hasn't had recalls but I believe it was missed since this is the second time with this same issue. This is a GM wide issue as I have researched.

ENGINE

I got off work started my truck heard a few pops. As I was driving the vehicle started jerking like the brakes were being applied. Then I noticed a yellow engine light and a ESC light come on. I pulled over to check vehicle and all the lights went off. Dealer was just a few miles away. So I started back up and drove to dealer. On the way to dealer vehicle started a tapping noise. Then a new message flashed something about my steering will be affected. I got I to dealer safely. Where I left the truck for repairs.

POWER TRAIN

We had to replace the transmission at 70,000 miles even though problems were reported to the dealer at 53,340. This repair costed $2300 on a 1 year old truck. Then we needed to replace a solenoid circuit which was not covered under warranty. We repaired this 2x (the second time covered). Then at 147,000 miles 9/24, there was a cylinder misfire which bent the push rod and collapsed lifter. This engine repair cost $8300.00 dollars. Who has to replace an engine on a truck that's 3 years old. This is a defect. Please help us. We have spent over $10,000 on repairs. We faithfully do our changes and service.

ENGINE

We had to replace the transmission at 70,000 miles even though problems were reported to the dealer at 53,340. This repair costed $2300 on a 1 year old truck. Then we needed to replace a solenoid circuit which was not covered under warranty. We repaired this 2x (the second time covered). Then at 147,000 miles 9/24, there was a cylinder misfire which bent the push rod and collapsed lifter. This engine repair cost $8300.00 dollars. Who has to replace an engine on a truck that's 3 years old. This is a defect. Please help us. We have spent over $10,000 on repairs. We faithfully do our changes and service.

ENGINE

Multiple injector and lifter failures. Occurred on 2 separate occasions. Taken to dealer the first time. Told injector failure and lifter failure. Less than a week later experienced multiple lifter failures. Taken to dealer again for repair. They only replaced some of the affected lifters, even though TSB from GM recommends replacement of all of them. Currently awaiting failure of additional components not replaced. There was no warning of either occurrence. Was only driving 45 mph on my way home the first time. The second occasion was on initial start up at Dr office. Opened a claim with GM on my own, as dealership was negligent or unwilling to contact GMC about these failures, even though I provided them with the appropriate TSB directly from GM.

ENGINE

Engine failed due to a loss of oil pressure. Rod bearing failed which cause metal to be dispersed throughout the engine causing the engine to seize from a sudden loss of oil pressure from oil pump failure. Engine was replaced in June 2024 failure happened in May 2024. While driving a system message came on DIC that stated pull over immediately to prevent engine damage and no oil pressure. I was driving uphill with cars on my right in the #2 lane. Engine shut off before I could pull over resulting in decreased braking power and a lack of steering. I almost hit 2 vehicles trying to pull over to get my family to safety on the right hand shoulder. I couldn’t pull over to the left hand shoulder as there was a guardrail in the way. When I got my vehicle pulled over the only thing that stopped my vehicle from going over the cliff was a bunch of wood chips on the right hand shoulder. From the time the warning lights came on to the time the engine shut off and seized was maybe 5 seconds. It took 31 days to replace the engine and the dealership did an inspection on the engine. There was absolutely no warning there was any problems until the lights came on. My wife and [XXX] and [XXX] were in the vehicle at the time this happened. It was so dangerous where we broke down California Highway Patrol stayed behind my vehicle with its lights on. It was also a fire hazard with the exhaust sitting on the dry bark. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

I purchased this vehicle new in 2021. It is an Ultimate Denali trim level with a 6.2 engine. Within the first year, the driver's side head on the engine had a massive failure with only 7,000 miles. I started up the vehicle and was parked idling briefly when several light came on along with a rough idle and some exhaust smoke. I contacted On Star, who could not diagnose the problem. The vehicle was disabled and ended up being towed to the dealer, where it was being repaired for 10 days. The lifters, valves and push rods were replace. The mechanic admitted there was an internal GM problem with the 6.2 engine. I asked for the same repair be made on the passenger side head. The GM dealer refused, knowing of the faulty factory installed parts. The polished tailpipe tips were not replace and were stained by the black exhaust. They are still stained this day. I purchased this vehicle for my retirement to tow my RV. Now, I have been reluctant to travel because of the other head letting go on me somewhere out west, operating under a work load. I know of two other people who purchased new GM vehicles with the 6.2 engine, who experienced the same failure, with around the same mileage on their vehicles.

ENGINE

at 8500 miles the engine had lifter go out while I was driving down the highway cause to truck to vibrate and becoming on unsteady causing me to pull over in the middle of traffic. later at 36500 miles it had another lifter go out this time I was driving home at a slower speed but still cause me to have to pull over vert fast as the vehicle became unsteady and vibrated causing all the alarm to come on. Both times the truck was fixed under warranty nut they replaced it with the same parts that are causing the problems. Soon my truck will be off warranty and this will come out of my pocket.

POWER TRAIN

L87 engine problems. I have had failed lifters, on top of transmission issues and a current oil consumption issue where I have to add two quarts of oil (sometimes more) without any indication of low oil. I took my vehicle into the local dealership and the technician asked if I had gotten any low oil indicator and I stated no. He proceeded to tell me it had little to no oil in it. Imagine this at highway speeds and sudden engine seizure.

ENGINE

L87 engine problems. I have had failed lifters, on top of transmission issues and a current oil consumption issue where I have to add two quarts of oil (sometimes more) without any indication of low oil. I took my vehicle into the local dealership and the technician asked if I had gotten any low oil indicator and I stated no. He proceeded to tell me it had little to no oil in it. Imagine this at highway speeds and sudden engine seizure.