LEAK NEAR 1-2 SERVO CASTING (4T60 A/T) REPLACE TRANS. CASE

TRANSMISSION APPLICATIONS: 1991 HYDRA-MATIC 4T60 (ME9)

TRANSMISSION MODELS: 1WFH, 1YSH, 1YTH, 1WJH, 1WMH 1WPH, 1WXH, 1WWH, 1YDH, 1YHH

SUBJECT: LEAK NEAR 1-2 SERVO CASTING SLOT - REPLACE CASE

VEHICLE APPLICATIONS: 1991 A, H, W, CAR

Bulletin Subject:

Transaxle fluid leak may be present due to a case crack near the 1-2 servo on some 1991 A, H, or W vehicles equipped with a 4T60 transaxle.

Service Information: (Figures 1, 2, and 3) ------------------------------------------- If the transaxle exhibits a leak near the 1-2 servo and was built between Julian Date 172 (June 17, 1991) and Julian Date 186 (July 28, 1991) and has a case casting die number of 594, stress cracks may be present. Inspect the case for stress cracks originating from the corner of the case casting slot. If cracks are present, the transaxle case must be replaced.

Service Parts Information:

Part Number Description Model Usage ----------- ----------- ----------- 8668986 Package, Transaxle Service 1WJH, 1WMH, 1WPH, 1WXH Case Assembly - Complete 1WWH, 1YDH, 1YHH

8668985 Package, Transaxle Service 1WFH, WYSH, WYTH Case Assembly - Complete

Parts are currently available from CANSPO.

Service Manual Reference:

Refer to the appropriate 1991 Service Manual for the proper case replacement procedure.

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.