SYS ONLINE INGEST 5 hours ago SOURCE NHTSA · TC BUILD v0.0.29
Vehicle scope Default: all classes — narrow to retail passenger anytime
Network/ Canada/ Mack/ 1984052

Mack · Canada · High

Mack Ultraliner, MH: Not Entered

Affects Mack Ultraliner, MH · 1982–1983 — about 38 vehicles.

The hazard

A CARBON STEEL CHECK VALVE SPRING WAS MISTAKENLY INSTALLED IN THE DUAL COMPARTMENT AIR RESERVOIR. USAGE OF CARBON STELL SPRINGS IN THIS APPLICATION CAN RESULT IN SEVERE CORROSION AND SUBSEQUENT FAILURE. IF A LEAK DEVELOPS IN THE PRIMARY AIR SYSTEM, AIR WOULD NOT BE CHECKED OR ISOLATED FROM THE FAILED SYSTEM AND AIR WOULD FLOW FROM THE SECONDARY SYSTEM AND EXHAUST AT THE POINT OF LEAKAGE RESULTING IN LOSS OF SERVICE BRAKES AND APPLICATION OF THE EMERGENCY SPRING BRAKES. IF THE DRIVER IGNORES THE LOW AIR PRESSURE WARNING LIGHT AND BUZZER AND FAILS TO PULL OFF THE ROAD, THE POSSIBILITY EXI

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