K 2500 Truck 4WD V6-262 4.3L (1988)
Crankshaft Main Bearing Seal: Customer Interest
Engine - Rear Main Leak Condition
SUMMARY NO. 256
TRUCK SERVICE BULLETIN 88-T-46R
Date:
January 19, 1988
SUBJECT:
REAR MAIN OIL LEAK DIAGNOSIS
MODEL:
1987 R/V, G, M AND 1988 C/K MODELS EQUIPPED WITH 4.3L (VIN CODE Z) ENGINES
Some 1987 R/V, G, M and 1988 C/K model trucks equipped with a 4.3L 6 cylinder engine (VIN Code Z) may experience a rear main oil seal leak
condition. A major symptom of this condition is leakage of engine oil at the rear of the engine.
To correct this condition and avoid potential repairs that could cost several hundred dollars, this bulletin describes new procedures for the repair of this
condition.
The estimated time for a GM dealer to perform this repair ranges from 2 to 4 hours. Dealer retail labor rates vary widely and could range from
approximately $17.00 to $32.00 per hour. The range may differ in some areas. Contact your local service facility for the actual labor rates.
This bulletin cancels and supersedes Truck Service Bulletin 88-T-7, dated March, 1987.
