GMC · Canada · Mod
GMC H8500, T6500: Powertrain
Affects GMC H8500, T6500 · 1979 — about 225 vehicles.
The hazard
VEHICLES EQUIPPED WITH CERTAIN DETROIT DIESEL ALLISON TRANSMISSIONS MAY HAVE IMPROPERLY MACHINED FORWARD CLUTCH HOUSINGS. THIS CONDITION AFFECTS OIL EVACUATION IN THE CLUTCH HOUSING AND MAY CAUSE THE VEHICLE TO MOVE FORWARD WHEN THE TRANSMISSION SELECTOR LEVER IS IN THE NEUITRAL POSITION.
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