CHUGGLE - (NEW CALIBRATION PROMS)

SUBJECT: CHUGGLE - NEW CALIBRATION PROM

MODELS/YEARS: 1992 CUSTOM CRUISER W/5.7L (VIN 7) ENGINE AND 2.73 AXLE (RPO GU2)

CONDITION: Some owners with vehicles listed below, equipped with 5.7L V8 engines, may comment about a "chuggle" condition.

This bulletin addresses the following vehicle/condition ONLY:

Vehicle Condition

Custom Cruiser Chuggle with base axle only RPO GU2, 2.73 ratio

CAUSE: Insufficient dampening of the torque converter and PROM calibration.

CORRECTION: New calibration PROMs have been released to address the above vehicle/condition. The following PROM is NOT RECOMMENDED for vehicles with OPTIONAL 3.23 AXLE RATIOS or TRAILER TOWING PACKAGES.

Emission Service Scan Broadcast System Year Axle Ratio/Body PROM P/N ID Code -------- ------- --------------- -------- ---- --------- Federal 1992 2.73 (GU2)/ 16195067 5131 BHHP (NA5) Custom Cruiser

Note: The above vehicles produced before December 16, 1991 (Julian Date 350) may have Hydra- Matic 4L60 Model 2DDM Transmissions. Model 2DDM transmissions may contain torque converters with insufficient dampening.

Vehicles with Model 2DDM transmission - Check dealer records to see if the torque converter has already been replaced with P/N 8650935 (tagged Broadcast Code: DGAF). It is not necessary to replace those torque converters with P/N 8650935.

Transmissions with torque converters with P/N 8656959 (tagged B/C: DG5F) need to have the torque converter replaced with P/N 8650935.

Model 2BRM transmissions P/N 8650935 (produced after December 16, 1991) have the new torque converter.

Parts are currently available from GMSPO.

WARRANTY INFORMATION:

Labor Operation Code Time --------------- ---- ---- Replace PROM T0500 0.6 hour Replace Torque Converter K7020 2.8 hours

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.