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:

    Viscosity Grade
    SAE 5W-30 is the best viscosity grade for the vehicle. Do not use other viscosity grade oils such as SAE 10W-30, 10W-40, or 20W-50. If in an area of extreme cold, where the temperature falls below &# ...

    New for 2010
    GM has dropped the long-running 6.0-liter V-8 engine from the Sierra lineup, leaving the powerful 6.2-liter V-8 for heavy towing needs. The rest of the Sierra's eight-cylinder lineup benefits from ...

    Radio(s)
    Radio with USB, CD, and DVD (MP3) : Press to turn the system on and off. Turn to increase or decrease the volume. BAND: Press to choose between FM, AM, or XM™, if equipped. : Select ra ...