030604017L

File in Section:
Bulletin No.:
Service Bulletin
Date:
06 - Engine
03-06-04-017L
September, 2017
INFORMATION
Subject:
Information on Diesel Fuel Additives
Models:
2014-2015 Chevrolet Cruze (RPO LUZ)
2017–2018 Chevrolet Cruze (Gen II — Vin B) (RPO LH7)
2016-2018 Chevrolet Colorado
2018 Chevrolet Equinox (RPO LH7)
2016-2018 Chevrolet Low Cab Forward 3500HD, 4500HD/XD, 5500HD/XD Medium Duty
2017-2018 Chevrolet Express (RPO LWN)
2016-2018 GMC Canyon
2018 GMC Terrain (RPO LH7)
2017-2018 GMC Savana (RPO LWN)
2018 and Prior GM Chevrolet and GMC Light Duty and Medium Duty Trucks
Attention: This Bulletin also applies to any of the above models that may be Export from North
America vehicles.
This Bulletin has been revised to add the 2018 Model Year. Please discard Corporate Bulletin
Number 03-06-04-017K.
Diesel Fuel Additives Are Not Required
or Recommended
The use of diesel fuel additives are not required or
recommended for the GM diesel engines under normal
conditions. The filtering system is designed to block
water and contaminants without the use of additives.
However, some customers may desire to use fuel
additives to improve the characteristics of available
diesel fuels. Refer to the Parts Information below.
Water Emulsifiers and Demulsifiers
If the customer desires to use a fuel additive, care must
be taken in its selection. There are two common
methods that fuel additives use to cope with water in
the fuel.
• One method is through demulsification of water in
the fuel. This method causes water particles to
combine together to form larger particles, which
drop out of suspension. This allows the fuel filter/
water separator to separate the water from the fuel
as it is designed to do.
• The other method of coping with water in the fuel
is through emulsification. This method, often using
alcohol as the emulsifier, keeps water particles
suspended in the fuel. Emulsification of water in
the fuel can allow water to get past the fuel filter/
water separator, in most cases causing damage to
other components of the fuel system.
Copyright 2017 General Motors LLC. All Rights Reserved.
Common Diesel Fuel Concerns
Fuel Waxing/Icing
Fuel distributors blend #1 and #2 diesel fuels* for
seasonal requirements in a particular region. No other
blending of fuels is recommended. However, a
customer may desire to use a winter fuel additive to
prevent fuel waxing or icing during extreme cold snaps.
If a winter fuel additive is to be used, it must not contain
any metal based additives, alcohol or other water
emulsifiers that may compromise the water removal
effectiveness of the fuel filtering system.
*In Canada, Diesel fuel blend #1 is categorized as type
A (Winter) and blend #2 is categorized as type B
(Summer)
Bacteria and Fungi Growth
Bacteria and fungi growth can occur in diesel fuel when
there is water present, especially during warmer
weather. The best prevention against bacteria and fungi
growth is to use clean fuel that is free of water. There
are diesel fuel biocides available which are designed to
kill bacterial growth in the fuel system. However, the
dead bacteria can still cause blockages throughout the
fuel system. If bacterial growth is found in the fuel
system, the proper method of removal is to flush the
fuel system using the appropriate Service Manual
procedures, replace the fuel filter element and refilling
the tank with clean diesel fuel. If a customer desires to
Page 2
September, 2017
use a biocide after flushing the fuel system, it must not
contain any metal based additives, alcohol or other
water emulsifiers.
Low Cetane Number
The cetane number is one indicator of a diesel fuel's
ability to ignite. There are many indicators of overall
fuel quality such as cleanliness, specific gravity,
volatility, viscosity, detergency, corrosion inhibiting
abilities, and lubricity. Increasing the cetane number
alone is not a fix for poor quality fuel. Additionally,
increasing the cetane number beyond the engine's
requirements will not increase performance. However,
the cetane number of diesel fuel is not always
consistent and some customers may desire to use a
cetane improver to ensure full performance of their
engine. If such an additive is to be used, it must not
contain any metal based additives, alcohol or other
water emulsifiers.
Poor Lubricity
The 2.0L diesel and the 6.6L Duramax® Diesel engines
are 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 their
fuel system components. If such an additive is to be
used, it must not contain any metal based additives,
alcohol or other water emulsifiers.
Fuel Stability
Fuel Stability and degradation may be a concern for
diesel fuels, especially for diesel fuel containing
biodiesel. Use of aftermarket stability additives to
improve quality of a degraded fuel is not a fix and use of
such aftermarket stability additives by customers is
discouraged due to concerns of proper mixing and fuel
Bulletin No.: 03-06-04-017L
compatibility. However some customers may desire to
use a stability additive to increase the shelf life of their
fuel. If such an additive is to be used, it must not
contain any metal based additives, alcohol or other
water emulsifiers.
Fuel Source Issue
If a vehicle is properly maintained but has fuel
contamination issues, consider obtaining fuel from a
different source. Purchasing fuel from a high volume
fuel retailer increases the chance that the fuel is fresh
and of good quality.
Parts information
GM ACDelco Diesel Fuel Conditioner
GM Diesel Fuel Conditioner®, P/N 88861698 (in
Canada, P/N 88861699) is alcohol free and metal free
additive. It is multifunctional additive and provides
benefits of cleaning engine deposits, improved lubricity,
improved cold temperature fuel flow, reduced fuel filter
plugging, corrosion protection, enhanced fuel stability
and cetane boost.
GM ACDelco Fuel System Treatment Plus
If the customer experiences concerns related to fuel
injector deposits, then it is allowed to use FUEL
SYSTEM TREATMENT PLUS® – DIESEL, P/N
88865597 (in Canada, P/N 88865600) based on
recommendation from the dealership technician. This is
a highly concentrated product and should be used as
per defined guidelines.
Duramax® is a Registered Trademark of General
Motors LLC (In the United States)
Duramax™ is a Trademark of General Motors LLC
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a
job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.
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