GMC Terrain: Customer Information / Customer Assistance Offices

GMC encourages customers to call the toll-free number for assistance. However, if a customer wishes to write or e-mail GMC, the letter should be addressed to:

United States and Puerto Rico

GMC Customer Assistance Center

P.O. Box 33172

Detroit, MI 48232-5172

www.gmc.com

1-800-GMC-8782 (1-800-462-8782)

1-888-889-2438 (For Text Telephone devices (TTYs))

Roadside Assistance:

1-888-881-3302

From U.S. Virgin Islands: 1-800-496-9994

Canada

General Motors of Canada Company

Customer Care Centre, Mail Code:

CA1-163-005

1908 Colonel Sam Drive

Oshawa, Ontario L1H 8P7

www.gmc.ca

1-800-263-3777 (English)

1-800-263-7854 (French)

1-800-263-3830

(For Text Telephone Devices (TTYs))

Roadside Assistance:

1-800-268-6800

Overseas

Please contact the local General Motors Business Unit.

    Customer Satisfaction Procedure

    Your satisfaction and goodwill are important to your dealer and to GMC. Normally, any concerns with the sales transaction or the operation of the vehicle will be resolved by your dealer's sales or service departments...

    Customer Assistance for Text Telephone (TTY) Users

    To assist customers who are deaf, hard of hearing, or speech-impaired and who use Text Telephones (TTYs), GMC has TTY equipment available at its Customer Assistance Center...

    Other information:

    GMC Terrain 2018-2026 Owners Manual: Checking Coolant


    The vehicle must be on a level surface when checking the coolant level. Check to see if coolant is visible in the coolant surge tank. If the coolant inside the coolant surge tank is boiling, do not do anything else until it cools down. If coolant is visible but the coolant level mark is not visible, add a 50/50 mixture of clean, drinkable water and DEX-COOL coolant at the coolant surge..

    GMC Terrain 2018-2026 Owners Manual: Vehicle Personalization


    The following are all possible vehicle personalization features. Depending on the vehicle, some may not be available. For System, Apps, and Personal features and functions, see “Settings” in the infotainment manual. To access the vehicle personalization menu: Touch the Settings icon on the Home Page of the infotainment display. Touch Vehicle to display a list of available optio..

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