Thousands of Mack trucks recalled for parking brake defect

December 27, 2021

Land Line Staff


Mack Trucks is recalling thousands of TerraPro trucks due to a parking brake issue.

Nearly 21,000 model year 2008-19 TerraPro (MRU) and 2019-22 TerraPro (TE) trucks are part of the recall.

According to the National Highway Traffic Safety Administration, a worn PP1 valve (park brake control valve) exhibiting an internal leak may cause air to pass through and out the exhaust port when the park brake is applied. Under certain conditions, the internal leak in combination with the installation of an exhaust hose may result in back pressure sufficient to allow the park brakes to release. The unexpected release of the parking brake may allow the vehicle to roll away, increasing the risk of a crash.

Mack Trucks will notify owners of the defect around Feb. 4. Dealers will remove the exhaust tube and fitting from the valve of affected TerraPro trucks for free.

For questions, call Mack customer service at 800-866-1177 with recall number SC0433. NHTSA’s number for this recall is 21V-953.

Mack Trucks was first notified of an incident involving a TerraPro truck in May 2019, prompting an investigation. NHTSA launched a preliminary evaluation to further investigate the issue in April 2020. In August, Mack received notice of another incident involving a TerraPro truck. A defect report was submitted to NHTSA on Dec. 9. LL