TTY Users
OnStar has the ability to communicate to the deaf, hard-of-hearing, or speech-impaired customers while in the vehicle. The available dealer-installed TTY system can provide in-vehicle access to all of the OnStar services, except Virtual Advisor and OnStar Turn-by-Turn Navigation.
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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Rear Towing (Rear Wheels Off the Ground)
Two-Wheel-Drive Vehicles
Use the following procedure to dolly tow a two-wheel-drive vehicle from the rear:
1. Attach the dolly to the tow vehicle following the dolly manufacturer's instructions.
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Using the 3.5mm (1/8 in) Auxiliary Input Jack
The auxiliary input jack is located on the lower right side of the faceplate.
This is not an audio output; do not plug a headphone set into the front auxiliary input jack. Connect an auxiliary input ...