Engine Stall Warning: Volvo and Mack Trucks Issue Recall

Volvo and Mack Trucks Issue Recalls Over Engine Stall Risk

Idler Gear Fastener Issue Sparks Safety Concerns

Volvo Trucks North America and Mack Trucks, Inc. have each issued separate but related recalls affecting a combined total of more than 100 heavy-duty trucks. The recalls stem from a manufacturing issue involving the idler gear bracket fasteners inside the turbo compound units. If these fasteners are not properly tightened, the idler gear can detach from the engine, potentially leading to a sudden engine stall and an increased risk of a crash.

The National Highway Traffic Safety Administration (NHTSA) announced both recalls on April 17, 2025.

Details on Volvo Trucks Recall

Volvo Trucks North America is recalling certain 2022–2025 Volvo VN and 2025 New VN model trucks. A total of 102 trucks in the United States are affected. According to the recall report, specific turbo compound units may have idler gear bracket fasteners that were improperly torqued during production or have missing torque records.

If the fasteners loosen, the idler gear can detach, causing significant engine damage. In the worst-case scenario, this could result in a loss of motive power while driving, increasing the chances of a crash or injury.

Owners of the affected Volvo trucks will be notified by mail starting on or before June 11, 2025. Dealers will inspect the vehicles and replace the turbo compound units if necessary, free of charge.

Volvo’s internal reference number for this recall is RVXX2504. Owners can also contact Volvo Trucks’ customer service at 1-800-528-6586 or the NHTSA Vehicle Safety Hotline at 1-888-327-4236.

Mack Trucks Also Impacted by Possibility of Engine Stall

Separately, Mack Trucks, Inc. issued a recall for three 2025 Mack Anthem (AN) vehicles built between September 24, 2024, and October 24, 2024. Like Volvo, Mack identified the same issue with the idler gear bracket fasteners inside certain turbo compound units.

Mack Trucks explained that improper torque or missing torque records during manufacturing could cause the fasteners to loosen, leading to possible engine damage and vehicle disablement. The resulting loss of engine power poses a crash risk.

Mack dealers will also inspect and replace the turbo compound units where needed at no cost to the truck owners. Owner notification letters are set to be mailed by June 11, 2025. The recall campaign is listed under Mack’s number SC0477. Mack’s customer service can be reached at 1-800-866-1177.

Engine Stall Investigation Timeline

The root cause for both recalls traces back to November 2024, when an engine returned for failure analysis revealed that the turbo compound idler gear bracket fasteners were not properly secured. This discovery prompted an engineering investigation by both companies.

By late November 2024, corrective actions were implemented in the manufacturing process to improve torque application and recordkeeping. However, a product safety investigation was later opened, and by April 2025, both Volvo’s and Mack’s Product Safety Committees decided to issue official recalls.

Notably, while Volvo Trucks reported 63 field reports connected to the issue, no accidents or injuries have been linked to either manufacturer so far.

What Truck Owners Should Watch For

Both recalls mention that an early warning sign could be an illuminated engine indicator lamp. Drivers might also notice the truck running roughly before any complete loss of power occurs.

Affected owners are encouraged to respond promptly once notification letters are received to schedule the necessary inspections and repairs.

How the Engine Stall Issue Has Been Corrected

Since late November 2024, production changes have been made to correct the torque control tooling. This adjustment ensures that fasteners are now properly tightened and verified during the assembly of new turbo compound units.

Replacement parts installed as part of the recall will have properly torqued idler gear bracket fasteners to prevent recurrence of the defect.

Additional Information Regarding the Engine Stall Issue

Truck owners seeking more information can contact Volvo or Mack customer service lines or visit the NHTSA website at nhtsa.gov. Owners may also report any safety concerns directly through the NHTSA Vehicle Safety Hotline.

Both manufacturers stressed their commitment to safety and encouraged all impacted vehicle owners to have their trucks inspected and repaired as soon as possible once notified.