Service brakes, air: supplyRecall 78V-008 · 1976–1977 Tmc MC8
TRANSIT MANUFACTURING,INC recall 78V-008 covers 527 1976–1977 Tmc MC8 for a service brakes, air: supply problem, reported to NHTSA on January 16, 1978.
Source: NHTSA recall 78V008000 and manufacturer quarterly reports. Started by the manufacturer.
The problem
THE INVOLVED VEHICLES MAY NOT COMPLY WITH FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, "MODULATED EMERGENCY BRAKING". THE "O" RINGS IN THE SHUTTLE VALVE MAY DEVELOP SLIGHT LEAKS IN COLD WEATHER. IN ADDITION, NEOPRENE WASHERS USED ON THESE "O" RINGS MAY EVENTUALLY EXPAND OR PUCKER IN COLD CLIMATES, MAKING IT POSSIBLE FOR THE SHUTTLE PISTON TO BECOME TRAPPED BY THE INNER-CIRCUMFERENCES OF THE WASHERS. THIS WOULD FORCE THE EMERGENCY BRAKES TO THE "ON" POSITION AND WOULD PREVENT THEM FROM BEING RELEASED.
The fix
THE DEALER WILL REPLACE THE TWO NEOPRENE WASHERS WITH GLASS FILLED TEFLON WASHERS THAT WILL NOT BE AFFECTED BY COLD CLIMATES.
VEHICLE DESCRIPTION: BUSES.SYSTEM: EMERGENCY BRAKES; SHUTTLE VALVE.CONSEQUENCES OF DEFECT: SHOULD THE EMERGENCY BRAKES BECOME LOCKED DURINGVEHICLE OPERATION, LOSS OF VEHICLE CONTROL AND AN ACCIDENT COULD RESULT.
Recall repairs are free. Confirm whether this recall is open on your vehicle by entering its VIN at nhtsa.gov/recalls.