Starting and Operating

See also:

Accessories and Modifications
Adding non-dealer accessories or making modifications to the vehicle can affect vehicle performance and safety, including such things as airbags, braking, stability, ride and handling, emissions syste ...

Heavy-DutyTrailer Wiring Harness Package
For vehicles equipped with heavy duty trailering, the harness connector is mounted in the bumper. The seven-wire harness contains the following trailer circuits: • Yellow: Left Stop/Turn Signal ...

Customer Satisfaction Procedure (U.S. and Canada)
Your satisfaction and goodwill are important to your dealer and to GMC. Normally, any concerns with the sales transaction or the operation of the vehicle will be resolved by your dealer's sales or ser ...