Mack Trucks, Inc. (Mack) is recalling certain 2016 Pinnacle CHU and CXU diesel trucks equipped with certain Dana steer axles. The castellated nut and cotter pin on the steer axles may not have been properly torqued, allowing the tie rod to loosen within the steer axle.

Consequence & remedy

Consequence: If the tie rod loosens, it may disconnect from the steering knuckle, causing a complete loss of steering, increasing the risk of a crash.

Remedy: Mack will notify owners, and dealers will inspect the torque of the castellated nut and tie rod, tightening it as necessary. If the tie rod stud and knuckle on units cannot be sufficiently torqued, the dealer will replace the knuckle and tie rod end assembly, free of charge. The recall began on October 17, 2017. Owners may contact Mack customer service at 1-800-866-1177. Mack's number for this recall is SC0408.

Additional source detail variants (2)

Steering:linkages:tie Rod Assembly

Consequence: If the tie rod loosens, it may disconnect from the steering knuckle, causing a complete loss of steering, increasing the risk of a crash.

Remedy: Mack will notify owners, and dealers will inspect the torque of the castellated nut and tie rod, tightening it as necessary. If the tie rod stud and knuckle on units cannot be sufficiently torqued, the dealer will replace the knuckle and tie rod end assembly, free of charge. The recall began on October 17, 2017. Owners may contact Mack customer service at 1-800-866-1177. Mack's number for this recall is SC0408.

Steering

Consequence: If the tie rod loosens, it may disconnect from the steering knuckle, causing a complete loss of steering, increasing the risk of a crash.

16V929000 · Suspension:front:hub

Dec 23, 2016

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.

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.