OnStar Additional Information
See also:
Vehicle Messages
Messages displayed on the DIC indicate the status of the vehicle or some action may be needed to correct a condition. Multiple messages may appear one after another.
The messages that do not require ...
Customer Assistance Offices (U.S. and Canada)
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
GMC Customer Assistance ...
What to Use
To determine what kind of fluid to use, see Recommended Fluids and Lubricants on page 11‑12. Always use the proper fluid.
Notice: Use of the incorrect fluid may damage the vehicle and the damag ...





