2026 Mack Granite Gr (4) problems, complaints & recalls
Safety recalls (2)
Service Brakes, Air:drum 2025-07-29 · campaign 25V495000 · 36 vehicles
Defect: Mack Trucks, Inc. (Mack) is recalling certain 2026 Mack GR trucks. The brake drum and steer axle combination are incompatible, which may cause a loss of brake function. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 121, "Air Brake Systems."
Risk: Reduced brake function can extend the distance required to stop, increasing the risk of a crash.
Fix: Dealers will replace the steer axle brake drums, free of charge. Owner notification letters were mailed August 27, 2025. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0482.
Service Brakes, Air:drum 2025-05-28 · campaign 25V352000 · 5 vehicles
Defect: Mack Trucks, Inc. (Mack) is recalling certain 2026 Granite trucks. The incorrect drive axle brake drums were installed, resulting in an incorrect load rating on the door jamb label.
Risk: Incorrect weight rating information on the door can result in overloading the axles, increasing the risk of a crash.
Fix: Dealers will replace the brake drums, free of charge. Owner notification letters were mailed June 16, 2025. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0472.
Service bulletins (20)
Technical service bulletins are repair instructions manufacturers send dealers for known issues. Unlike recalls, the fix is not automatically free — but naming the bulletin at the service desk can save diagnosis time and support goodwill repairs.
Electrical System 2026-09-27 · TSB M-373-003 202609 · Service Bulletin/Repair Instructions
power cable alternator replacement
Electrical System 2026-09-17 · CBR 2483-6 202609 · Service Bulletin/Repair Instructions
diagnostic instructions for can network communication issues.
Electrical System 2026-09-01 · TSB M-371-005A 202609 · Service Bulletin/Repair Instructions
jumper harness repair for version 4 mack trucks
Engine 2026-06-22 · CBR-2592-1 202606 · Service Bulletin/Repair Instructions
the purpose of this cbr is to provide steps on how to correct a customer complaint of dtc p107b86 accompanied with intermittent loss of throttle.
Seat Belts 2026-05-29 · GDC26-02 202605 · Service Bulletin/Repair Instructions
fault diagnostic information for supplemental restraint / airbag inflation system (srs)
Power Train 2026-04-25 · GDC26-001 202604 · Over The Air
gdc - transmission oil level sensor
Showing the 6 most recent of 20 bulletins. Search all of them free at nhtsa.gov.
What owners report
No detailed complaint narratives on file.
Excerpts of consumer complaints filed with NHTSA, lightly truncated. They are owner statements, not verified findings.