Mack Trucks is recalling 628 model year 2009-2015 Granite (GU) trucks due to incorrectly installed brake chambers that may cause brake imbalance and overheating. The National Highway Traffic Safety Administration assigned the campaign number 25V867 to the recall, which Mack is tracking internally as SC0491.
Highlights
- 628 Mack Granite trucks from model years 2009-2015 are affected by incorrect brake chamber installations following a previous recall remedy
- Brake imbalance between steer and drive axle brakes may cause rear brakes to overheat, increasing the risk of tire blowout or wheel-end fire
- Dealers will inspect and replace undersized brake chambers free of charge, with owner notifications expected by February 2, 2026
- No crashes, injuries, or warranty claims have been reported in connection with this defect
Defect Details
The recall stems from inaccurate dealer service information that was not updated following the completion of a previous recall, SC0398 (NHTSA 15V804). Vehicles that received repairs after that recall was completed may have had incorrect brake chambers installed due to erroneous parts data in the dealer service system.
The incorrect brake chambers can create an imbalance between the steer axle and drive axle braking systems. This imbalance may cause the rear brakes to overheat during operation.
NHTSA warns that overheated brakes increase the risk of a tire blowout or fire, which could lead to a crash. The agency has issued consumer advisories recommending affected owners not drive their vehicles and park them outside until repairs are completed.
Affected Components
Volvo Trucks North America, the OEM supplier, manufactured the brake chambers involved in this recall. The affected components include:
- CS30 (Part No. 85143550)
- TR3030T (Part No. 5554-3431951)
- GC3030LCW (Part No. 85145824)
- SC30LCW (Part No. 5396-SC30LCW)
- GC3030CW (Part No. 5396-GC3030CW)
Discovery Timeline
A fleet customer first alerted a Volvo service manager to incorrect part information in the dealer service system on October 31, 2025. A subsequent fleet inspection on November 5 confirmed that multiple vehicles had received incorrect parts during post-recall repairs.
The Safety Office was notified the following day and opened a formal product safety investigation on November 20. After review by the Product Safety Evaluation Committee on December 2, the matter was escalated to the Product Safety Committee, which determined on December 9 that a safety defect existed.
Mack reported no warranty claims, field reports, accidents, or injuries associated with this condition at the time of the recall filing.
Remedy Program
Authorized dealers will inspect affected vehicles to verify correct brake chamber installation. Any undersized chambers will be replaced with components matching correct engineering specifications at no cost to owners.
Dealer notifications are scheduled for December 22, 2025. Owner notification letters are expected to be mailed by February 2, 2026.
Owners who previously received a remedy under Recall 15V804 (SC0398) must have the new remedy completed.
Vehicle Identification Numbers involved in this recall will be searchable on NHTSA.gov beginning December 22, 2025. Owners may contact Mack customer service at 1-800-866-1177 with questions.
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