3-2 COASTDOWN CLUNK/THM 125-C BROKEN SERVO CUSHION SPRING

MODELS AFFECTED: 1983 THM 125-C TRANSMISSION

Some 1983 THM 125-C transmissions may exhibit a 3-2 coastdown clunk condition that is most noticeable at approximately 18 miles per hour when decelerating. The clunk my feel like a bump or harsh downshift. This 3-2 coastdown clunk condition may be caused by a broken intermediate servo cushion spring.

Beginning August 16, 1983, a new intermediate servo cushion spring (Part No. 8652057) went into production for the following THM 125-C transmission models:

The past spring was blue in color, while the new spring is violet. When servicing any THM 125-C transmission models listed above for a 3-2 coastdown clunk condition, follow the service procedure given below:

1. Refer to your service manual for disassembly and reassembly procedures.

2. Remove the intermediate servo cushion spring and visually inspect it for cracks, breaks, or damage.

3. If the intermediate servo cushion spring is cracked, broken, or damaged, replace it with part number 8652057.

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.