GM Service Manual Online
For 1990-2009 cars only

OIL EXHAUSTING FROM VENT 200C & 400 TRANSMISSION

Some THM 200C and 400 model transmissions may experience oil exhausting from the transmission oil vent. This condition may be caused by the pump to case attaching bolts bottoming in the threaded bolt holes in the case.

If any 200C or 400 THM transmissions are being serviced for this condition refer to the following service procedure.

SERVICE PROCEDURE

1. Remove the converter from the transmission.

2. Check the pump to case attaching bolts for proper torque (20.0-27.0 N.m or 15-20 ft. lbs.).

3. If the bolts are found not to be up to torque specifications, remove all six (6) of the bolts and grind 1/8 inch (3.18mm) off the end of the bolts, leaving the ends as square as possible.

4. Replace the bolts after grinding and torque to 20.0-27.0 N.m (15-20 ft. lbs.).

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.