K 1500 Truck 4WD V8-305 5.0L (1988)
Clutch: All Technical Service Bulletins
A/T - 4L60 Steel 3-4 Clutch Plate Availability
Number:
91-112-7A
Section:
7A
Date:
November 1990
Corp. Bulletin No.: 077138
Subject: NEW 3-4 CLUTCH PLATES
Model and Year:
1987-91 CAPRICE, CAMARO, CORVETTE WITH 4L60 AUTOMATIC TRANSMISSION
1987-91 C/K, G, M, R/V, S/T TRUCK AND 1990-91 L TRUCK WITH 4L60 AUTOMATIC TRANSMISSION
TO:
ALL CHEVROLET DEALERS
BULLETIN COVERS:
New 3-4 clutch plates (steel) are available for 1987-1990 HYDRA-MATIC 4L60 transmissions. The new clutch plates have a slightly smaller outer
radius to let them move more freely in the clutch housing.
DATE OF PRODUCTION CHANGE:
Beginning July 27, 1990 (Julian Date 208), all HYDRA-MATIC 4L60 transmissions were built using the new 3-4 clutch plates.
SERVICE INFORMATION:
The new 3-4 clutch plates can be used to service any HYDRA-MATIC 4L60 transmission produced after February 9, 1987 (Julian Date 040).
SERVICE PARTS INFORMATION:
Description
New Part #
Plate - 3rd and 4th (steel - 4 or 5 needed)
8678053
Plate - 3rd and 4th (steel - 1 needed)
8678054
Parts are currently available from GMSPO.
SERVICE MANUAL REFERENCE:
Refer to the Automatic Transmission Unit Repair Section of the appropriate service manual for 3-4 clutch plate removal and installation information.