Engine and engine cooling: engine: engine control module (ECU/ECM): software
Manufacturer
Mack Trucks, Inc.
Vehicles affected
775
Reported to NHTSA
2026-03-11
Owners notified
2026-04-14
Defect description
Mack Trucks, Inc. (Mack) is recalling certain 2022-2027 TerraPro trucks. The engine control unit (ECU) software may allow the engine to start when the transmission is not in Neutral. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 102, "Transmission Shift Lever Sequence, Starter Interlock, and Transmission Braking Effect."
Safety risk
Starting the vehicle while in gear may cause unexpected vehicle movement, increasing the risk of a crash or injury.
Manufacturer remedy
Dealers will update the ECU software, free of charge. Owner notification letters were mailed April 14, 2026. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0492. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov March 18, 2026.
Mack Trucks, Inc. (Mack) is recalling certain 2010-2018 MRU and 2019-2025 Terrapro towing vehicles. The vehicles are missing the anti-lock brake (ABS) warning light and circuitry that controls the anti-lock brake function for an attached trailer. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 121, "Air Brake Systems."
Safety risk
Driving without a functioning anti-lock brake system may result in the trailer not braking as intended, increasing the risk of a crash.
Manufacturer remedy
Dealers will add an ABS warning light and circuitry, free of charge. Owner notification letters were mailed April 28, 2025. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0474.
Mack Trucks, Inc. (Mack) is recalling certain 2020-2025 Anthem, Granite, TerraPro and Pinnacle vehicles, equipped with Bendix EC80 Advanced Electronic Control Units (ECU). Electrical noise and low signal to the power line carrier may cause the ECU to incorrectly process commands or stop working.
Safety risk
Safety systems that depend on the ECU (Automatic Traction Control, ABS, Electronic Stability Control, Active Cruise Control, and Collison Mitigation System) may have diminished or lost functionality, increasing the risk of a crash.
Manufacturer remedy
Dealers will reprogram the ECU software, free of charge. Owner notification letters were mailed December 9, 2024. Owners may contact Mack customer service at 1-800-866-1177. Mack's number for this recall is SC0472.
Mack Trucks, Inc. (Mack) is recalling certain 2024-2025 MD and Terrapro vehicles. The Gross Axle Weight Rating (GAWR) listed on the vehicle certification label is incorrect, which can allow the vehicle to be overloaded. As such, these vehicles fail to comply with the requirements of 49 CFR Part 567, "Certification."
Safety risk
An overloaded vehicle can increase the risk of a crash.
Manufacturer remedy
Dealers will remove and replace the label, free of charge. Owner notification letters were mailed May 28, 2024. Owners may contact Mack customer service at 1-800-866-1177. Mack's number for this recall is SC0463.
Mack Trucks, Inc. (Mack) is recalling certain 2024 Anthem, Pinnacle, and Terrapro vehicles. The steering gear assemblies may have been assembled incorrectly with fewer recirculating balls than are required, which may result in a loss of steering control.
Safety risk
A loss of steering control increases the risk of a crash.
Manufacturer remedy
Dealers will inspect and replace the defective gears as necessary, free of charge. Owner notification letters were mailed February 9, 2024. Owners may contact Mack customer service at 1-800-866-1177. Mack's number for this recall is SC0457.
Mack Trucks, Inc. (Mack) is recalling certain 2023-2024 GR, AN, LR, and Terrapro vehicles. The engine may not return to idle within 2 seconds if the accelerator pedal position sensor becomes disconnected. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 124, "Accelerator Control Systems."
Safety risk
An engine that does not return to idle quickly enough can cause a loss of vehicle control, increasing the risk of a crash.
Manufacturer remedy
Mack will replace the throttle pedal and update the vehicle software, free of charge. Owner letters were mailed February 27, 2024. Owners may contact Mack customer service at 1-800-866-1177. Mack's number for this recall is SC0455.
Mack Trucks, Inc. (Mack) is recalling certain 2024 Granite and TerraPro vehicles. The rear lifting bracket that attaches to the engine cylinder head may be insufficiently secured, which can allow it to detach.
Safety risk
A rear lifting bracket that detaches while the engine is being lifted can result in the engine falling or swinging, increasing the risk of injury.
Manufacturer remedy
Dealers will inspect and replace the flanged stud in the rear lifting bracket, as necessary, free of charge. Owner notification letters were mailed December 9, 2023. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0452.
Owner complaints
A complaint is one person's report to a federal agency. It is not a finding.
No complaints recorded for this model year.
Safety recall repairs are provided free of charge by franchised dealers, regardless of vehicle age or mileage. This page displays aggregated data for the model year. To check recall status for a specific vehicle, search its VIN at nhtsa.gov.