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.

Consequence & remedy

Consequence: 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.

Remedy: Mack will notify owners, and dealers will replace the hub assemblies, free of charge. The recall began on February 16, 2017. Owners may contact Mack customer service at 1-800-866-1177. Mack's number for this recall is SC0406.

16V099000 · Power Train:driveline:driveshaft

Feb 19, 2016

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.

Consequence & remedy

Consequence: 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.

Remedy: Mack will notify owners, and dealers will replace the cap nut. The input shaft threads will be inspected for damage. Any damaged input shaft will be replaced. These repairs will be performed free of charge. An interim notice was sent to owners on April 25, 2016. The recall began on June 7, 2016. Owners may contact Mack customer service at 1-610-709-2131. Mack's recall campaign number for this recall is SC0399.

15V644000 · Trailer Hitches:fifth Wheel Assembly

Oct 13, 2015

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.

Consequence & remedy

Consequence: 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.

Remedy: Mack will notify owners, and Fontaine dealers will replace the fifth wheel with an Ultra NT model fifth wheel, free of charge. The recall began on November 18, 2015. Owners may contact Mack customer service at 1-800-866-1177. Mack's number for this recall is SC0395.

Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗

NHTSA investigations

PE20005 · Mdrive Transmission Failure To Disengage

Opened Apr 28, 2020 · Closed Apr 4, 2022

Status: closed (inferred from source dates) · Power Train:manual Transmission

On April 28, 2020, the Office of Defects Investigation (ODI) opened PE20-005 to investigate reports of 2013-2015 Mack CHU and CXU trucks equipped with mDrive transmissions continuing to push forward when stopping, possibly increasing the risk of a crash. After more field reports were discovered, the scope of the investigation was expanded to cover MY 2013-2016 vehicles. The mDrive transmission is Mack's version of Volvo's I-Shift transmission, an automated manual transmission that allows gear shifting without the use of a clutch pedal. Early I-Shift transmissions were recalled (13V-268) to address a missing redundant clutch disengagement switch that could prevent the clutch from automatically disengaging when the brake was applied. If a loss of signal from the brake air pressure switch occurred, the clutch would remain engaged while braking.Although Mack's mDrive transmission adopted the latest Volvo I-Shift design and was built with the redundant clutch switch, ODI received field reports alleging that the mDrive transmission would not disengage when coming to a stop like the Volvo I-Shift transmissions in recall 13V-268.After more than a year of information requests, data exchanges and grouping, and analyzing data, ODI was able to correlate two versions of transmission software (ID 23084009 and ID 23084004), with two frequently replaced parts ('solenoid valve' and 'cylinder assy clutch') as outliers. However, Mack dismissed the replacement parts as being normal service parts for worn clutch systems.According to Mack, unlike the I-Shift recall, loss of one or more of the switches would not keep the clutch engaged but might cause a delay in the clutch disengaging, possibly due to the software/control system settings, the worn parts and system reaction time.To demonstrate the possible switch failure outcomes, Mack outfitted a subject model truck with a panel that could disable each switch on command. During test drives at the Mack facility, the demonstrator truck stopped when the brake was applied each time, and the truck did not stall when the brake was applied, even when the clutch was engaged. Even though failure of one of the switches could delay clutch disengagement, the stopping distance would still be shorter than one of the recalled Volvo I-Shift transmission trucks. With this information, as well as a lack of known crash incidents related to this complaint, ODI concludes that the Mack vehicles do not present an unreasonable risk to motor vehicle safety. Although ODI is closing this PE, Mack/Volvo should continue improving the transmission control unit software to further refine the clutch disengagement strategy. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. Claims are still being submitted and the Agency will continue to monitor the issue and reserves the right to take further action if warranted by new circumstances.