Introduction
See also:
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 ...
Different Size Tires and Wheels
If wheels or tires are installed that are a different size than the original equipment wheels and tires, vehicle performance, including its braking, ride and handling characteristics, stability, and r ...
Engine Oil
To ensure proper engine performance and long life, careful attention must be paid to engine oil.
Following these simple, but important steps will help protect your investment:
• Always use engine ...





