2012 MACK GRANITE (GU)

POWER TRAIN:DRIVELINE:DRIVESHAFT

Mack Trucks, Inc. (Mack) is recalling certain model year 2012-2016 Granite (GU), Pinnacle (CHU, CXU), TerraPro (LEU, MRU), Titan (TD), and LR trucks manufactured from September 1, 2011, through September 8, 2015. The cap nut that retains the interaxle driveshaft yoke to the rear axle input shaft may loosen.

Risk: If he cap nut loosens and falls off, the yoke can separate from the axle input shaft and allow the drive shaft to disconnect, increasing the risk of a crash.

SUSPENSION:FRONT:HUB

Mack Trucks, Inc. (Mack) is recalling certain model year 2012, 2014-2015 and 2017 Granite (GU), 2012-2017 Pinnacle (CHU, CXU), and 2013-2015 and 2017 Titan (TD) trucks manufactured January 7, 2011, to September 29, 2016. The affected vehicles were built with front wheel hubs that cannot support the gross axle weight rating of the front axle.

Risk: Overloaded front wheel hubs can result in premature failure of the hubs, bearings, and the related components, which can cause the front hub assembly to separate from the front axle. Because of this, the driver may lose control of the vehicle or parts may be dropped on the road, increasing the risk of a crash.

ENGINE AND ENGINE COOLING:ENGINE:OTHER FUEL TYPES:TURBO/SUPERCHARGER

Mack Trucks, Inc. (Mack) is recalling certain model year 2010-2016 Granite (GU), LR, and TerraPro (LEU, MRU) trucks manufactured November 17, 2009 to October17, 2015. The affected trucks have engines with a turbocharger oil supply line that may contact or interfere with the turbocharger inlet elbow, clean air intake clamp, or the air fuel control tube, and result in an oil leak.

Risk: If the turbocharger oil supply line oil leaks in the proximity of the engine exhaust manifold there would be an increased risk of a fire.

SERVICE BRAKES, AIR:SUPPLY:RESERVOIR/TANK

Mack Trucks, Inc. (Mack) is recalling certain model year 2011-2016 Granite (GU) trucks manufactured September 24, 2011, to July 1, 2015. The affected trucks may be equipped with an air brake system reservoir that does not have a sufficient volume. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 121, "Air Brake Systems."

Risk: If the air brake system reservoir has as insufficient volume, braking performance may be affected, increasing the risk of a crash.

SERVICE BRAKES, AIR:SUPPLY:HOSES, LINES/PIPING, AND FITTINGS

Mack Trucks, Inc. (Mack) is recalling certain model year 2013 and 2015 Titan (TD), model year 2014 and 2015 Pinnacle (CHU), and model years 2009-2010, 2012, and 2014-2016 Granite (GU) trucks. The chassis harness and air lines may not be properly clipped to the crossmember, which can allow the cables and air lines to fall and get twisted in the driveline.

Risk: If the electrical cables and air lines were to fall and get tangled in the driveline, it could affect the electrical system and braking system, increasing the risk of a vehicle crash.

SERVICE BRAKES, AIR:DISC:CHAMBER

Mack Trucks, Inc. (Mack) is recalling certain model year 2010-2016 Granite 4X2 trucks manufactured September 17, 2009, to July 31, 2015. Due to a brake imbalance between the steer and drive axle brakes, the rear brakes may overheat.

Risk: If the rear brakes overheat there would be an increased risk of a tire blowout or a wheel-end fire.

EXTERIOR LIGHTING:TURN SIGNAL:FLASHER UNIT

Mack Trucks Inc. (Mack) is recalling certain model year 2010-2014 CHU, CXU, and MRU, 2007 CT and CV, 2008-2014 GU, and 2011-2014 LEU, and TD trucks manufactured February 28, 2006, through November 8, 2013, and equipped Hamsar Electronic Flasher. The hazard warning lights may fail.

Risk: A failure of the hazard warning lights could reduce the trucks visibility, increasing the risk of a crash.

ELECTRICAL SYSTEM

Mack Trucks, Inc. (Mack) notified the agency on February 20, 2014, that they are recalling certain model year 2010-2012 CHU, CXU, GU and TD vehicles manufactured from June 16, 2009, through July 8, 2011. While continuing to research the scope of the issue, Mack expanded the recall on November 18, 2014 to include certain model year 2008-2009 and 2013-2014 CHU, CXU, GU and TD vehicles manufactured from June 16, 2009, through July 8, 2011. Having completed its investigation, Mack once again expanded the recall during February 2015 to include an additional 53,780 vehicles from model years 2007 and 2015. The recall now covers model year 2007-2015 includes CHU, CXU, GU and TD vehicles produced October 13, 2006, through October 3, 2014. In the affected vehicles, the Electronic Power Distribution Module (EPDM) may be contaminated from water leaks in, and around, the windshield. If exposed to water leaks, contaminants such as road salts may deposit on the EPDM.

Risk: Deposits of contaminants may result in the circuits being bridged, creating a high resistance short, increasing the risk of a fire.

VISIBILITY:WINDSHIELD WIPER/WASHER:LINKAGES

MACK IS RECALLING CERTAIN MODEL YEAR 2012 CHU, CXU, AND GU VEHICLES, MANUFACTURED FROM OCTOBER 10, 2011, THROUGH NOVEMBER 17, 2011. HARDWARE USED TO SECURE THE WINDSHIELD WIPER LINKAGE TO THE WIPER MOTOR MAY NOT BE SUFFICIENTLY TORQUED, AND MAY CAUSE THE WINDSHIELD WIPER LINKAGE TO DETACH FROM THE WIPER MOTOR. AS A RESULT, THE WINDSHIELD WIPERS WILL NOT FUNCTION.

Risk: IF THIS OCCURS, UNDER CERTAIN DRIVING CONDITIONS THE DRIVER'S VISIBILITY WILL BE REDUCED, INCREASING THE RISK OF A CRASH.

SERVICE BRAKES, AIR:SUPPLY:CHECK VALVE

MACK IS RECALLING CERTAIN MODEL YEAR 2012-2013 GU, MANUFACTURED FROM DECEMBER 2, 2010, THROUGH JANUARY 18, 2012, AND EQUIPPED WITH BENDIX ATR-6 TRACTION RELAY VALVES. IN EXTREMELY COLD CONDITIONS, THESE BENDIX RELAY VALVES MAY POTENTIALLY DEVELOP INTERNAL LEAKAGE. INTERNAL LEAKAGE CAN LEAD TO AIR PRESSURE BEING DELIVERED TO AFFECTED PRIMARY OR SECONDARY BRAKE CAUSING CONTINUOUS BRAKE APPLICATION.

Risk: INADVERTENT BRAKE APPLICATION CAN CAUSE THE BRAKES TO OVERHEAT AND LEAD TO A FIRE. INADVERTENT BRAKE APPLICATION CAN CAUSE THE WHEELS TO LOCK-UP LEADING THE DRIVER TO LOSE CONTROL OF THE VEHICLE, INCREASING THE RISK OF A CRASH.

POWER TRAIN:DRIVELINE

MACK TRUCKS IS RECALLING CERTAIN MODEL YEAR 2012, CHU, CXU, GU, MRU, LEU, AND TD TRUCKS EQUIPPED WITH A MERITOR DRIVELINE. THE TUBING USED TO ASSEMBLE THE AFFECTED DRIVELINES HAS A NONCONFORMING SEAM WELD WITH INSUFFICIENT BONDING OF THE MATERIAL.

Risk: THIS CAN RESULT IN SEAM WELD FRACTURE WHEN TORQUE IS APPLIED. ONCE THE TUBE SEAM WELD IS FRACTURED, THE DRIVELINE MAY BECOME INOPERABLE WHICH MAY RESULT IN A DISABLED VEHICLE OR DEBRIS FROM THE DRIVELINE MAY FALL ON THE ROADWAY, BOTH OF WHICH CAN INCREASE THE RISK OF A CRASH.