SYS ONLINE INGEST 6 hours ago SOURCE NHTSA · TC BUILD v0.0.29
Vehicle scope Default: all classes — narrow to retail passenger anytime
Network/ Canada/ Mack/ 1977167

Mack · Canada · High

Mack RS, WL +2 more: Not Entered

Affects Mack RS, WL, RL, WS · 1976–1978 — about 7 vehicles.

The hazard

TRUCKS EQUIPPED WITH ANCHORLOCK AIR DRYERS. A DESIGN DEFICIENCY EXISTS IN THE AIR DRYER PIPING THAT CAN ALLOW MOISTURE FROM THE COMPRESSED AIR TO FREEZE ALLOWING A BUILD UP OF EXCESSIVE AIR PRESSURE THAT WOULD CAUSE THE AIR PIPING CONNECTIONS TO SEPARATE. THIS WOULD LEAD TO AN AUTOMATIC APPLICATION OF THE CHASSIS EMERGENCY SPIRNG BARKES AND TRAILER BREAKES, WITHOUT WARNING, AND POSSIBLY CAUSE A LOSS OF VEHICLE CONTROL.

What to do

Contact your dealer; the remedy details were not included in the filing.

Critical — crash/injury risk now High — injury risk; see remedy Moderate — fix at next service Low — minor / informational