NEW DIRECT CLUTCH HOUSING SERVICE INFORMATION

MODELS AFFECTED: ALL 1985, 1986, 1987, 1989, AND 1990 WITH 3T40 THM125C TRANSAXLES

BULLETIN COVERS

A new Direct Clutch Drum (610) with an increased wall thickness of 0.2 mm (Figure 1) to prevent the Direct Clutch Drum from warping when subject to excessive heat caused by an Intermediate Band distress (606).

DATE OF PRODUCTION CHANGE

The new Direct Clutch drum went into production July 11, 1989, (Julian Date 192) for all Willow Run built transaxles and July 12, 1989, (Julian Date 193) for all Windsor built HYDRA-MATIC 3T40 transaxles.

SERVICE PROCEDURE

This new Direct Clutch Drum can be used on previous model HYDRA-MATIC 3T40 transaxles built since (model year) Start of Production - 1985. Do not attempt to use the new Direct Drum in transaxles built previous to model year 1985 because the return spring and snap ring groove location will not allow 1980 thru 1984 model internal components to assemble into the new direct clutch drum.

If an intermediate band failure occurs, inspect the outer wall of the direct clutch drum using a flat edge ruler. If there are dips in the drum between the ruler, the drum should be replaced.

SERVICE PARTS INFORMATION

Whenever ordering a New Direct Clutch Housing, refer to the following part numbers:

Part Number Description ----------- ----------- 8653971 Direct Clutch Drum and Check Ball Capsule

8653982 Direct Clutch Drum, Check Ball Capsule and Intermediate Band

Refer to GMSPO group number 4.251 for proper usage. Parts are currently available from GMSPO.

SERVICE MANUAL REFERENCE

Whenever servicing any THM 125C/HYDRA-MATIC 3T40 transaxle, refer to the procedures outlined in the Unit Repair Section of your Service Manual.

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.