NHTSA recall 85V113000
Service brakes, air
Mack MH
Reported Sep 17, 19855,020 vehicles affectedMACK TRUCKS, INCORPORATEDBuilt Jan 1, 1982 – Dec 1, 1984
The defect
The dual double check valve may not release the proper air volume to the brake system, causing a slight timing delay between the tractor and the trailer brake system. consequences of defect: if the brakes are suddenly applied, the trailer could jackknife without warning to the operator, which could result in a vehicle crash.
The remedy
Install two new sleeves in the dual double check valve which will increase air flow.