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 ...

Trailer Gain and Output
On vehicles with the Integrated Trailer Brake Control (ITBC) system, the trailer brake display appears in the DIC. Press the vehicle information button until TRAILER GAIN and OUTPUT display. TRAILER ...

OnStar®
If the vehicle is equipped with an active OnStar system, that system may also record data in crash or near crash-like situations. The OnStar Terms and Conditions provides information on data collectio ...