Other Navigation Services Available from OnStar
OnStar eNav: Allows subscribers to send destinations from Google Maps™ and MapQuest.com to their Turn-by-Turn Navigation or screen-based navigation system.
When ready, the directions will be downloaded to the vehicle.
Destination Download: Push 
, then request the Advisor to download directions to the navigation system in the vehicle.
After the call ends, push the “Go” button on the navigation screen to begin driving directions.
Destinations can also be downloaded on the go. For information about eNav, Destination Download, and coverage maps visit www.onstar.com.
See also:
Recommended Fluids, Lubricants, and Parts
Recommended Fluids and Lubricants
Maintenance Replacement Parts
Replacement parts identified below by name, part number, or specification can
be obtained from your dealer.
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Cellular and GPS Antennas
Avoid placing items over or near the antenna to prevent blocking cellular and GPS signal reception. Cellular reception is required for OnStar to send remote signals to the vehicle. ...
Roadside Assistance Program
U.S.: 1-888-881-3302
TTY Users (U.S.): 1-888-889-2438
Canada: 1-800-268-6800
Mexico: 01-800-466-0801
As the owner of a new GMC, you are automatically enrolled in the Roadside Assistance program.
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