A/T - Driveline Clunk During Garage Shift/Acceleration
89chevy34Number: 90-86-7D
Section: 7D
Date: November 1989
Corporate Bulletin No.: 977150
Subject: DRIVELINE CLUNK DURING GARAGE SHIFT OR HARD ACCELERATION
Model and Year: 1990 C TRUCKS WITH 4L60/3L80/5LM60/HM-117 FORT WAYNE PRODUCED TRANSMISSIONS
TO: ALL CHEVROLET DEALERS
This bulletin covers service and parts information for vehicles which may exhibit a clunking noise during a garage shift or a driveline clunk during hard acceleration. Vehicles may be affected if they were built at the Fort Wayne Plant and are within the following VIN number ranges:
1GCDC14K2LZ100013 - 1GCDC14Z2LZ101290
Figure 1:
This condition can be repaired by installing a reinforcement plate in the tailshaft crossover support Figure 1.
To install the reinforcement plate, remove the nut and washer from the underside of the transmission crossmember. Install reinforcement plate onto the bolt that passes through crossmember and replace the washer and nut. Torque the nut 54 N-m (40 lb.ft.).
Part Name Part Number
Reinforcement Plate 15567681
Parts are currently available from GMSPO.
This information is not contained in any Service Manual.