Silverado Classic 3500 4WD V8-6.6L DSL Turbo (2007)
Drive Belt: All Technical Service Bulletins
Diesel Engine - Chirp/Squeal On Cold Start Idle
Bulletin No.: 07-06-01-003
Date: March 07, 2007
TECHNICAL
Subject:
LBZ LB7 LLY 6.6L Duramax(R) Diesel Engine Accessory Drive Belt Chirp, Squeal, or Squeak Type Noise at Cold Start Idle (Replace Accessory Drive
Belt)
Models:
2002-2007 Chevrolet Silverado (Classic)
2006-2007 Chevrolet Express
2003-2007 Chevrolet Kodiak C4500/C5500 Series
2002-2007 GMC Sierra (Classic)
2006-2007 GMC Savana
2003-2007 GMC TopKick C4500/C5500 Series
with 6.6L Duramax(R) Diesel Engine (VINs D, 1, 2 - RPOs LBZ, LB7, LLY)
Attention:
Do not replace the accessory drive belt for a chirp noise during engine shutdown. This is a normal condition for a diesel engine.
Condition
Some customers may comment on an accessory drive belt chirp, squeal, or squeak type noise at idle, especially on a cold start. The noise may be reduced
or go away after the engine warms up.
Correction
Refer to Service Bulletin Number 05-06-01-018A. Follow the service procedures outlined in the bulletin to diagnose and repair an accessory drive belt
chirp, squeal, or squeak type noise at cold idle.
If the noise was not fully eliminated by the service procedures outlined in the bulletin in step 1, then replace the accessory drive belt with a second design
belt that may be less prone to noise.