2012 MACK PINNACLE (CXU)

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.

TRAILER HITCHES:FIFTH WHEEL ASSEMBLY

Mack Trucks, Inc. (Mack) is recalling certain model year 2011-2014 Pinnacle (CHU and CXU) trucks manufactured September 10, 2010, to June 17, 2013. The affected trucks are equipped with Fontaine Ultra LT Fifth Wheel connectors, which, due to cumulative damage to the fifth wheel and its locking mechanism, have a locking mechanism that may fail to operate or to properly engage.

Risk: If the fifth wheel and locking mechanism are sufficiently damaged, the locking mechanism may fail to operate as intended and the trailer may unexpectedly detach from the tractor, increasing the risk of a crash.

TRAILER HITCHES:FIFTH WHEEL ASSEMBLY

Mack Trucks, Inc (Mack) is recalling certain model year 2012-2015 CXU trucks manufactured February 4, 2011, to December 23, 2014, and equipped with an air release fifth wheel latch. The affected vehicles have a switch to release the fifth wheel latch that may invertently be pushed and cause the trailer to unintentionally disconnect from the tractor after the parking brake has been released.

Risk: An inadvertent decoupling of the trailer from the tractor may increase the risk of a crash.

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.

EXTERIOR LIGHTING

Mack Trucks Inc. (Mack) is recalling certain model year 2010-2015 CXU trucks manufactured November 20, 2009, through January 27, 2014, and equipped with dual vertical exhaust pipes. The white conspicuity reflectors on the rear of the cab could be blocked by the exhaust pipes. As such, these vehicles do not conform to Federal Motor Vehicle Safety Standard (FMVSS) number 108, "Lamps, Reflective Devices, and Associated Equipment."

Risk: A blocked reflector makes the truck-tractor less visible when operating the vehicle without a trailer in the dark, 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.

PARKING BRAKE:CONVENTIONAL:AIR

Mack Trucks, Inc. is recalling certain model year 2011-2013 CXU trucks manufactured November 23, 2010, through March 19, 2012. These vehicles are equipped with an MGM Type 24 J-series piston parking brake chamber. In the affected axles, the brake chambers may leak pressure allowing the parking brake to drag when it is supposed to be released. Brake dragging could lead to overheated brake components.

Risk: Overheated brake components could result in 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.

TRAILER HITCHES:FIFTH WHEEL ASSEMBLY

MACK TRUCKS IS RECALLING CERTAIN MODEL YEAR 2011-2012 CXU TRUCKS MANUFACTURED FROM MAY 1, 2010, THROUGH JANUARY 31, 2011. DURING THE COUPLING PROCESS, IT IS POSSIBLE FOR THE DRIVER TO PARTIALLY CLOSE THE FIFTH WHEEL LOCK AND IF SOLELY RELYING ON A TUG TEST (PULL TEST), THE DRIVER MAY THINK THAT THE FIFTH WHEEL LOCK IS PROPERLY COUPLED TO THE TRAILER KING PIN WHEN IN FACT IT IS NOT PROPERLY COUPLED.

Risk: IF THE DRIVER DRIVES AWAY WITH A TRAILER THAT IS NOT PROPERLY COUPLED, THE TRAILER CAN COME LOOSE AND POTENTIALLY RESULT IN A VEHICLE 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.