Recommended Fuel
Use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, an audible knocking noise, commonly referred to as spark knock, might be heard when driving.
If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. If heavy knocking is heard when using gasoline rated at 87 octane or higher, the engine needs service.
See also:
OnStar Mobile App
With an iPhone® or Android™-based mobile device, an OnStar mobile app can be
downloaded. The vehicle can be remote started, if equipped, or the doors can be
unlocked from anywhere there is cell ...
Compass Recalibration
This display allows for calibrating the compass. See Compass on page 5‑6 for more information. ...
Customer Assistance for Text Telephone (TTY) Users (U.S. and Canada)
To assist customers who are deaf, hard of hearing, or speech impaired and who use Text Telephones (TTYs), GMC has TTY equipment available at its Customer Assistance Center. Any TTY user can communicat ...