For 1990-2009 cars

# HARD/HARSH 1-2 SHIFT AT FULL THROTTLE (NEW CONTROL VALVE)

TRANSMISSION APPLICATIONS: SUBJECT: ------------------------- ------- 1988 THM 125C (MD9) HARSH 1-2 SHIFTS AT WIDE OPEN THROTTLE

TRANSMISSION MODELS: VEHICLE APPLICATIONS: ------------------- -------------------- KDC 1988 N CARS EQUIPPED WITH 2.3L ENGINES

(Revised to Correct Date of Production.)

#### BULLETIN COVERS:

A new control valve assembly with a new 1-2 accumulator spring, valve and bushing went into production to reduce the potential for a harsh 1-2 upshift. This upshift may occur during wide open throttle in a 1988 0512N car equipped with a KDC model THM 125C transaxle. This condition may be repaired by installing a 1-2 accumulator valve train.

DATE OF PRODUCTION CHANGE: (Figure 1) -------------------------- Beginning November 10, 1987 (Julian Date 314) all 1988 THM 125C KDC model transaxles were built with the new 1-2 accumulator spring (313) bushing (314) and valve (315). (Refer to Figure 2)

#### SERVICE PARTS INFORMATION:

Package No. Package Description ---------- ------------------- 8664964 (1) Pin, Valve Spring Retaining (304) (1) Valve, 1-2 Accumulator (315) (1) Bushing, 1-2 Accumulator (314) (1) Spring, 1-2 Accumulator (313) (1) Instruction Sheet

SERVICE MANUAL REFERENCE: (Refer to Figure 2) ------------------------ When servicing any 1988 THM 125C transaxle for this condition refer to the 1988 THM 125C (MD9) Automatic Transaxle Unit Repair section in 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.