Driving Information
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 ...
Call Waiting
Call waiting must be supported on the cell phone and enabled by the wireless service carrier.
• Press to answer an incoming call when another call is active. The original call is placed on hold.
...
Treadwear
The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would wear ...





