K 2500 Truck 4WD V8-379 6.2L DSL VIN C FI (1989)
Clutch: All Technical Service Bulletins
A/T - 4L60 New 3-4 Clutch Plates Available
GMC NUMBER:
91-7A-33
GROUP:
7A Automatic Transmission
DATE:
November, 1990
CORPORATE
NUMBER:
077138
SUBJECT:
NEW 3-4 CLUTCH PLATES (STEEL)
MODELS:
1987-91 C/K, R/V, S/T LIGHT DUTY TRUCKS AND G, M/L VANS WITH 4L60 AUTOMATIC TRANSMISSIONS
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 (Juliann Date 040).
SERVICE PARTS INFORMATION:
Description
New Part
Quantity
Number Required
Plate-3rd and 4th (steel)
8678053
4 or 5
Plate-3rd and 4th (steel)
8678054
1
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.
