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.

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    Setting Cruise Control
    If the cruise button is on when not in use, it could get bumped and go into cruise when not desired. Keep the cruise control switch off when cruise is not being used. The cruise control light on the ...

    Liftgate
    To open the liftgate the vehicle must be in P (Park). Press the touch pad under the liftgate handle. To close the liftgate, use the pull cup or pull strap as an aid. Power Liftgate On vehicles with ...

    Powertrain details
    The GMC Sierra All Terrain HD concept is propelled by the new, production 6.6L Duramax turbo-diesel V-8 and Allison 1000 six-speed automatic transmission powertrain combination offered in the 2011 ...