C 2500 Suburban 2WD V8-6.5L DSL Turbo VIN F (1995)
Technical Service Bulletin # 99-06-04-047C
Date: 070103
Diesel Fuel System - Fuel Lubricity/Metal Contamination
Bulletin No.: 99-06-04-047C
Date: January 03, 2007
INFORMATION
Subject:
Information on Low Fuel Lubricity and Fuel System Metal Contamination
Models:
2002 and Prior Light Duty and Medium Duty Trucks
with 6.5L V8 Diesel Engine (VINs F, P, S - RPOs L65, L49, L56)
Attention:
Multiple fuel tank removals or fuel system cleaning is not needed. Please follow this diagnosis process thoroughly and complete each step. If the
condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
Supercede:
This bulletin is being revised to update the parts and warranty information. Please discard Corporate Bulletin Number 99-06-04-047B (Section 06 -
Engine/Propulsion System).
Low fuel lubricity may be a concern. Recommend to the customer on a new fuel injection pump break-in period to use Stanadyne lubricity additive for
two or three tanks of fuel or 3200 km (2000 mi).
Metal contaminants generated by fuel injection pump internal component degradation are returned to the fuel tank. The in-tank strainer filtering
capability is sufficient to prevent the reintroduction of these contaminants into the fuel system. Metal contaminants generated by frame mounted lift
pump internal component degradation will be trapped in the fuel filter.
If the repair history shows fuel injection pump replacement with multiple fuel system cleaning, check the fuel filter for metal contamination. If the fuel
filter shows minimal metal contamination, replace the fuel filter and follow the Stanadyne Lubricity Additive information in this bulletin. A small amount
of metal contamination does not necessitate a fuel system cleaning.
Diagnosis of Fuel Related Concerns
A small amount of metal contamination is normal and not detrimental to the operation of the diesel engine. Do not remove the fuel tank for cleaning
unless the in-tank fuel strainer is plugged with sediment or plugged with various metal contaminants. Do not clean the fuel system unless the fuel filter is
plugged with sediment or plugged with various metal contaminants. Evidence of some metal contamination does not necessitate fuel system cleaning. In
some cases, fuel system degradation over time or fuel contamination by fueling the vehicle may collect large amounts of metal or other types of
contamination in the fuel tank and is not covered under warranty. The fuel system cleaning procedure in this bulletin, if needed, is divided into three
service categories.
Check the repair history on the vehicle. If the vehicle is a 2000 through 2002 year model, and a new pump has been installed, refer to Repair Procedure
Number 1 for Fuel System Cleaning in this bulletin.
Check the repair history on the vehicle. If the vehicle is a 1994 through 1999 year model, but has already had an updated pump installed, refer to Repair
Procedure Number 2 for Fuel System Cleaning in this bulletin.
For 1994 through 1996 year models, with no repair history, refer to Repair Procedure Number 3 for Fuel System Cleaning in this bulletin.
1997 or newer vehicles should not need the fuel system cleaned. Refer to the Stanadyne Lubricity Additive Information in this bulletin.
If the fuel system is contaminated with anything else than metal, follow the guidelines found on Special Policy 00064F.
All questions about how the additive is charged out on the repair order are to be directed to the dealers AVM (DSM in Canada).
All questions about out of warranty 6.5L fuel injection pumps and fuel system cleaning are to be directed to the dealer's AVM (DSM in Canada).
Refer to GM Service Bulletin Number 03-06-04-017A or newer for further information on Diesel Fuel Additives.
The 6.5L diesel engine is designed to operate on today's low sulfur fuel without the use of additives. A fuel additive designed to increase lubricity is not a
fix for poor quality or contaminated fuel, but some customers may desire to use a lubricity additive to aid in the longevity of the fuel system components.
