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Info - Non-GM Parts and Accessories (Aftermarket)

Subject:Non-GM Parts and Accessories (Aftermarket)

Models:2007 and Prior Passenger Cars and Trucks (Including Saturn)
2007 and Prior HUMMER H2, H3
2005-2007 Saab 9-7X



This bulletin is being updated to add models and model years. Please discard Corporate Bulletin Number 04-06-04-054 (Section 06 - Engine).


The recent rise and expansion of companies selling non-GM parts and accessories has made it necessary to issue this reminder to dealers regarding GM's policy on the use and installation of these components.

When a dealer is performing a repair under the New Vehicle Limited Warranty, they are required to use only genuine GM or GM-approved parts and accessories. This applies to all warranty repairs, special policy repairs or any repairs paid for by GM. Parts and accessories advertised as being "the same" as parts manufactured by GM, but not sold through GM, do not qualify for use in warranty repairs, special policy repairs or any repairs paid for by GM.

During a warranty repair, if a GM original equipment part is not available through GMSPO, ACDelco® distributors, other GM dealers or approved sources, the dealer is to obtain comparable, non-GM parts and clearly indicate, in detail, on the repair order the circumstances surrounding why non-GM parts were used. The dealer must give customers written notice, prior to the sale or service, that such parts or accessories are not marketed or warranted by General Motors.

It should also be noted that dealers modifying new vehicles and installing equipment, parts and accessories obtained from sources not authorized by GM are responsible for complying with the National Traffic and Motor Vehicle Safety Act. Certain non-approved parts or assemblies, installed by the dealer or its agent not authorized by GM, may result in a change to the vehicle's design characteristics and may affect the vehicle's ability to conform to federal law. Dealers must fully understand that non-GM approved parts may not have been validated, tested or certified for use. This puts the dealer at risk for potential liability in the event of a part or vehicle failure. If a GM part failure occurs as the result of the installation or use on a non-GM approved part, the warranty will not be honored.

A good example of non-authorized modification of vehicles is the result of an ever increasing supply of after market devices available to the customer, which claim to increase the horsepower and torque of the Duramax™ Diesel Engines. These include the addition of, but are not limited to one or more of the following modifications:

    • Propane injection
    • Nitrous oxide injection
    • Additional modules (black boxes) that connect to the vehicle wiring systems
    • Revised engine calibrations downloaded for the engine control module
    •  Calibration modules which connect to the vehicle diagnostic connector
    • Modification to the engine turbocharger waste gate

Although the installation of these devices, or modification of vehicle components, can increase engine horsepower and torque, they may also negatively affect the engine emissions, reliability and/or durability. In addition, other powertrain components, such as transmissions, universal joints, drive shafts, and front/rear axle components, can be stressed beyond design safety limits by the installation of these devices.

General Motors does not support or endorse the use of devices or modifications that, when installed, increase the engine horsepower and torque.

These same policies apply as they relate to the use of non-GM accessories. Damage or failure from the use or installation of a non-GM accessory will not be covered under warranty. Failure resulting from the alteration or modification of the vehicle, including the cutting, welding or disconnecting of the vehicle's original equipment parts and components will void the warranty.

Additionally, dealers will NOT be reimbursed or compensated by GM in the event of any legal inquiry at either the local, state or federal level that results from the alteration or modification of a vehicle using non-GM approved parts or accessories.

Dealers should be especially cautious of accessory companies that claim the installation of their product will not void the factory warranty. Many times these companies have even given direction on how to quickly disassemble the accessory in an attempt to preclude the manufacturer from finding out that is has been installed.

Any suspect repairs should be reviewed by the Area Service Manager (District Service Manager in Canada) for appropriate repair direction. If it is decided that a goodwill repair is to be made on the vehicle, even with the installation of such non-GM approved components, the customer is to be made aware of General Motors position on this issue and is to sign the appropriate goodwill documentation required by General Motors.

It is imperative for dealers to understand that by installing such devices, they are jeopardizing not only the warranty coverage, but also the performance and reliability of the customer's vehicle.