2013 MACK PINNACLE (CXU)

STEERING

Mack Trucks, Inc. (Mack) is recalling certain model year 2013 Pinnacle (CXU) trucks manufactured April 16, 2012, to May 4, 2012. These vehicles are equipped with certain Meritor FF967 non-drive front steer axles that may have been incorrectly heat treated.

Risk: The improperly heat treated axles may fracture, resulting in a loss of vehicle control and increasing the risk of a crash.

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.

SERVICE BRAKES, AIR:DISC:CHAMBER

Mack Trucks, Inc. (Mack) is recalling certain model year 2013-2015 Pinnacle (CXU) trucks manufactured from October 3, 2012, through February 18, 2014 and equipped with Meritor air disc brakes. In the affected vehicles, the brake chambers may have been incorrectly mounted resulting in internal contamination of the air brake calipers.

Risk: Contamination of the calipers may cause a loss of brakes on one wheel, lengthening the distance required to stop the vehicle, 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.

FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL

Mack Trucks, Inc. (Mack) is recalling certain model year 2013-2015 CXU and 2014-2015 CHU trucks manufactured August 23, 2012, through June 27, 2014, and equipped with adaptive cruise control. Due to a software error, the affected vehicles may not provide visual or audible alerts to the driver warning them that an obstruction in the road was detected.

Risk: If the driver is not warned of something being in the truck's path, there is an increased risk of a crash.

POWER TRAIN:AXLE HUBS

Mack Trucks is recalling certain model year 2013-2014 CHU, CXU, GU, LEU, and MRU vehicles manufactured with pro-torque axle spindle nuts from August 28, 2012, through August 16, 2013. The pro-torque nut may not have been installed correctly, which may result in a loosening of the nut.

Risk: If the nut comes loose, the hub assembly may separate from the vehicle, increasing the risk of a crash.

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.