HARSH 1-2 UPSHIFT INSTALL SERVICE PACKAGE

SUBJECT: HARSH 1-2 UPSHIFT-INSTALL SERVICE PACKAGE

MODELS/YEAR: 2 CUSTOM CRUISER, BRAVADA

CONDITION:

--------- Some vehicles equipped with a 1992 HYDRA-MATIC 4L60 transmission built between Julian Date 061 (March 1, 1992) and Julian Date 171 (June 19,1992) may exhibit a harsh 1-2 upshift.

Note: Once the transmission is brought to operating temperature, the condition may not be able to be reproduced until a 'cold soak' (overnight) is performed. This correction is not intended to modify a firm 1-2 shift on vehicles equipped with towing packages (RPO U92).

CAUSE:

----- The above condition may be caused due to a tapered 1-2 accumulator sleeve. The tapered bore may cause the 1-2 accumulator valve to stick in the bottom of the bore.

CORRECTION:

---------- To improve the 1-2 shift, install the appropriate service package listed below. A 1-2 accumulator valve and 1-2 accumulator valve sleeve (which, normally, is not serviceable) is included in the package.

PARTS INFORMATION:

Package Number Transmission Models -------------- ------------------- 8687992 2BAM, 2BBM, 2BCM, 2BHM, 2BRM, 2BWM, 2TLM, 2TWM,

8688900 2TAM, 2TBM

Parts are currently available from GMSPO.

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.