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For 1990-2009 cars only

REVISED:NEW TRANSAXLE GASKET AND VALVE BODY COVER

Model and Year: 1980-86 125 and 125C TRANSAXLE

Beginning June 6, 1985, or Julian Date 157, all 1985 models of the THM 125 and 125C transaxle are being produced using new gaskets for the oil pan and valve body cover. The new gaskets improve sealing capability by better with- standing fastener torques.

When servicing 1980 through 1984 THM 125 and 125C transaxles built to September, 1983 (1984 model year, Julian Date 244), refer to Hydra-matic Product Service Bulletin HM 83-70, which describes the use of a new oil pan and valve body cover incorporating a raised rib on the flange. Make sure, that the service parts packages called for in HM 83-70 (Part Nos. 8653942 and 8653943) contain the new latex-coated cellulose (hard, fiber material) gasket. Some service parts packages may contain the latex-coated cork (soft material) gasket, which should not be used.

When servicing 1984 through 1986 THM 125 and 125C transaxles built after September, 1983 for oil pan and/or valve body cover fluid leaks, refer to the following procedure:

SERVICE PROCEDURE

1. Diagnose source of fluid leak to be certain leak is from the transaxle oil pan and/or valve body cover (refer to the correct Service Manual section).

2. If leak is determined to be from the transaxle oil pan and/or valve body cover area:

A. Remove the oil pan and/or valve body cover.

B. Clean the case, oil pan and/or valve body cover faces (with solvent) and visually inspect for damage and/or presence of gasket material.

C. Make sure all gasket material is removed from the case, oil pan and/or valve body cover faces.

3. Replace the transaxle oil pan and/or valve body cover gasket(s) with:

PACKAGE NO. QUANTITY DESCRIPTION ----------- -------- ----------- 8660038 1 Transaxle Oil Pan Gasket 8660039 1 Transaxle Valve Body Cover Gasket

4. When replacing the oil pan and/or valve body cover, it is critical that a torque wrench is used to tighten the hex head screws. Hand torque all hex head screws 12-16 N.m (9-12 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.