SERVICE BRAKES, AIR:SUPPLY:HOSES, LINES/PIPING, AND FITTINGS
AIR SYSTEM BLOCKAGE IN THE AIR DRYER OCCURS DEGRADING THE MOISTURE REMOVING CAPABILITIES OF THE DRYER WHEN THE VEHICLE IS OPERATED IN A COLD ENVIRONMENT AND MOISTURE ACCUMULATES AND FREEZES IN THE AIR DRYER OR IN THE LINE BETWEEN THE DRYER AND THE AIR SYSTEM RESERVOIR. THE AIR DRYER CAN BECOME OVERPRESSURIZED CAUSING THE AIR DRYER CARTRIDGE TO SEPARATE FROM THE MOUNTING BASE.
Remedy: DEALERS WILL EQUIP AIR SYSTEMS WITH A PRESSURE RELIEF VALVE TO BE LOCATED BETWEEN THE COMPRESSOR AND THE AIR DRYER. THIS PRESSURE RELIEF VALVE IS INTENDED TO VENT IF EXCESSIVE PRESSURE DEVELOPS IN THE AIR DRYER.
1,224 vehicles affected
TRAILER HITCHES
THE CARRIER YOKE BOLTS WERE MANUFACTURED WITH WORN ROLLING THREAD DIES, CAUSING STRESS CONCENTRATIONS WHICH CAUSED CRACKS DURING THE QUENCHING PROCESS.
Remedy: REPLACE THE CARRIER YOKE BOLTS.
4,924 vehicles affected