C 2500 Suburban 2WD V8-350 5.7L VIN K TBI (1995)
PROM - Programmable Read Only Memory: All Technical Service Bulletins
Engine - Cold Knock, Replace Oil Filter/Bearings/PROM
File In Section: 6 - Engine
Bulletin No.: 37-61-05A
Date: October, 1995
Subject:
Cold Engine Knock (Replace Oil Filter/Bearings/PROM)
Models:
1990-95 Chevrolet and GMC Truck C/K, R/V, S/T, M/L, G, P Models
1991-92 Oldsmobile Bravada
with 4.3L (VIN Z - RPO LB4), 5.7L (VIN K - RPO L05),
7.4 (VIN N - RPO L19) Engine
This bulletin is being revised to add the 1995 model year information. Please discard Corporate Bulletin Number 37-61-05 (Section 6 - Engine).
Condition
Some late model truck engines have been reported to exhibit "cold knock" on start up. "Cold Knock" usually occurs after the vehicle has been
completely warmed up, then parked for 8 or more hours in ambient temperatures of 35° F or less. "Cold knock" can be separated into three distinct
categories.
1.
Short Duration - Harsh, deep metallic knock that usually lasts from 1 to 10 seconds. Generally classified as a bearing or rod knock.
2.
Valve Train - Light clatter, tick or click that may last up to 1 minute.
3.
Piston Slap - Metallic knock that occurs only under load. Piston slap may last as long as 5 minutes.
Correction
Category A: Short Duration Knock
This matrix describes the repair for each affected model year and engine.
Specific information for each affected model year and engine is supplied.