Basic Trailer Wiring
All regular, extended cab and crew cab pickups have a seven-wire trailer towing harness.
For vehicles not equipped with heavy duty trailering, the harness is secured to the vehicle's frame behind the spare tire mount. The harness requires the installation of a trailer connector, which is available through your dealer.
If towing a light-duty trailer with a standard four-way round pin connector, an adapter is available from your dealer.
See also:
Roadside Assistance Program
U.S.: 1-888-881-3302
TTY Users (U.S.): 1-888-889-2438
Canada: 1-800-268-6800
Mexico: 01-800-466-0801
As the owner of a new GMC, you are automatically enrolled in the Roadside Assistance program.
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Ending a Call
Press to end a call. ...
Driver Information Center (DIC)
The DIC display is located in the center of the instrument panel cluster. It
shows the status of many vehicle systems.
The DIC buttons are located below the climate control system.
MENU: Press thi ...