OnStar Services
See also:
Shifting In or Out of Neutral
1. With the vehicle running and the engine at an idle, set the parking brake.
2. Place the transmission into N (Neutral).
Shift the transfer case in one continuous motion into or out of the N (Neutr ...
Automatic Dimming
If equipped with an automatic dimming mirror, the driver outside mirror adjusts for the glare of the headlamps behind you. See Automatic Dimming Rearview Mirror on page 2‑17. ...
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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