Campaign - Soft Crankshaft Sprockets: Overview

GMC NUMBER: 93-C-11(A)
GROUP: 6A Engine Mechanical
DATE: June 1993

Subject:
Soft Crankshaft Sprockets (no Heat-treat)

Models:
1993 C/K, G, P TRUCKS WITH 7.4L ENGINES (VIN CODE N)

This Bulletin Cancels And Replaces 93-C-11 Issued June 1993. Destroy All
Copies Of 93-C-11.

Revisions Include An Added Step To The Service Procedure And Changes In The Warranty Information.

General Motors has determined that CERTAIN 1993 C/K, G and P trucks with the 7.4L gas engines may have been built with soft crankshaft sprockets. A non-hardened sprocket will have excessive wear and could cause an engine failure.

To prevent this failure from occurring, dealers are to replace the crankshaft sprocket. In the event that the truck is towed in and it is determined that the crankshaft sprocket has failed, the engine should be replaced. To replace the engine, call your Technical Assistance Department for a new engine replacement. DO NOT order engine from General Motors Service Parts Operation (GMSPO).