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INTERMITTENT NO REVERSE MUST SHIFT TO DRIVE FIRST

TRANSAXLE APPLICATIONS: SUBJECT: ---------------------- ------- 1984-1987 THM 440-T4 INTERMITTENT NO REVERSE OR LOCKS IN REVERSE

TRANSAXLE MODELS: VEHICLE APPLICATIONS: ---------------- -------------------- ALL A, C, H, E, K CARS

Bulletin Covers:

A 1984 through 1987 vehicle equipped with a THM 440-T4 transaxle may have an intermittent no reverse or locking in reverse condition until shifted to a forward range prior to shifting into reverse ("unloading" the parking pawl). This condition may be caused by a "dent" on the parking pawl that does not allow the pawl to release until "unloaded".

DATE OF PRODUCTION CHANGE: (Figure 1) -------------------------- Effective May 1, 1987 (Julian date 121) all 1987 THM 440-T4 transaxles were produced with parking pawl assemblies not having a "dent".

SERVICE ACTION: (Figures 2 and 3) --------------- Remove transaxle and replace the Final Drive Internal Gear/Parking Pawl Assembly (#673) and Actuator Guide, Plunger and Spring Assembly (#709 - #711). Also inspect the Parking Gear for wear or damage and replace if necessary.

SERVICE PARTS INFORMATION:

Part Number Description ----------- ----------- 8656372 Final Drive Internal Gear/Parking Pawl Assembly 8656689 Actuator Guide, Plunger and Spring Assembly 8658416 Parking Gear

SERVICE MANUAL REFERENCE:

Refer to appropriate Service Manual for repair information.

SERVICE NOTES: (Figure 2) -------------- Before installing the replacement parts, inspect the new Final Drive Internal Gear/Parking Pawl Assembly to make sure it does not have a "dent".


Object Number: 80514  Size: FS


Object Number: 79285  Size: FS


Object Number: 78134  Size: FS

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.