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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    What to Use
    WARNING Adding only plain water or some other liquid to the cooling system can be dangerous. Plain water and other liquids, can boil before the proper coolant mixture will. The coolant warning sy ...

    Vehicle Overview
    GMC's Terrain is the twin to the Chevrolet Equinox. The five-seat crossover comes in front- or all-wheel drive with a four-cylinder or V-6 engine. Competitors include the Ford Escape, Toyota RAV4 ...

    Average Economy
    Press the trip/fuel button until AVG ECONOMY displays. This display shows the approximate average liters per 100 kilometers (L/100 km) or miles per gallon (mpg). This number is calculated based on the ...