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:

    Trailer-Tow Mirrors
    If the vehicle has towing mirrors, they can be adjusted for a clearer view of the objects behind you. Manually pull out the mirror head to extend it for better visibility when towing a trailer. Th ...

    Power Seats
    To adjust a power seat, if equipped: • Move the seat forward or rearward by sliding the control forward or rearward. • If available, raise or lower the front or rear part of the seat cushion ...

    Engine Oil
    For diesel engine vehicles, see “Engine Oil” in the Duramax Diesel Supplement. To ensure proper engine performance and long life, careful attention must be paid to engine oil. Following these si ...