OIL FROM VENT / THM125 AUX. VALVE BOLTS MAY BOTTOM

Some 1982 and 1983 THM 125C transmissions may experience a condition where oil exhausts from the transmission vent. This condition is a result of the bolts that attach the auxiliary valve body cover to the auxiliary control valve assembly, bottoming out in the bolt hole threads in the auxiliary control valve assembly. The bolts will obtain the original bolt torque, but will not clamp the cover tight to the auxiliary control valve assembly, leaving a gap. Oil will then leak, and exhaust out the transmission vent.

When servicing any THM 125C transmission for this condition, refer to the following service procedure.

SERVICE PROCEDURE

1. Remove the valve body cover and gasket (or RTV sealant).

2. Replace the four auxiliary valve body cover attaching bolts with four shorter M6x1.0 x 20mm bolts (P/N 8643250) that are also used in attaching the servo cover to the case. Torque the bolts to 11 N.m (8 ft. lbs.).

3. Install the valve body cover and gasket (or RTV sealant).

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.