Silverado 3500 2WD V8-6.6L DSL Turbo VIN 2 (2004)
Air Cleaner Fresh Air Duct/Hose: Customer Interest
Diesel Engine - Runs Hot Towing or Pulling Grades
Bulletin No.: 06-06-04-036D
Date: June 04, 2007
TECHNICAL
Subject:
Engine Overheats or Runs Hot in High Ambient Temperature When Towing or Hauling on Long Inclines (Install 2006 Air Cleaner Assembly)
Models:
2004-2005 Chevrolet Silverado 2500/3500 Series
2004-2005 GMC Sierra 2500/3500 Series
with 6.6L Diesel Engine VIN 2 - RPO LLY)
Built From January 1, 2004 Through 2005 End of Production
Supercede:
This bulletin is being revised to clarify steps 10 and 11 and the illustration in step 10 of the procedure. Please discard Corporate Bulletin Number
06-06-04-036C (Section 06 - Engine/Propulsion System).
Condition
Some customers may comment that while towing a trailer, or if the vehicle is loaded on a long upgrade climb and high ambient temperatures, the Driver
Information Center states Engine Coolant Hot, the engine overheats and there is a loss of power and air conditioning.
Cause
This condition may be caused by any of the following possibilities:
Installation of an aftermarket grille.
A plugged charge air cooler.
Fan clutch not operating properly.
Drive belt slip.
An overfilled transmission.
Turbocharger not operating properly.
A plugged air filter.
Correction
Inspect the following areas FIRST.
Inspect for changes to the air intake area or for aftermarket grille accessories. Make sure all air dams are in place and not modified. Remove any
aftermarket grille or accessories that may restrict air flow.
Visually inspect the Charge Air Cooler (CAC) to insure that it is not plugged externally. Use the Special Tool J 46091 to ensure that all pipe connections
are properly sealed and the CAC does not have a leak.
Monitor the fan clutch operation and complete SI Diagnostics for Fan Clutch Diagnosis. If the fan seems to be cycling on and off when the engine RPMs
are above 2800, this could indicate a belt slip condition.
Monitor the actual and desired turbo vane position to verify that the turbocharger is performing properly.
Inspect the transmission fluid level. An overfilled transmission can add to heat levels in the cooling system.
Inspect the air induction system. Ensure that the filter is in good condition and is properly installed.
