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.com
The website provides access to account information, manages the OnStar subscription, and allows viewing of videos of each service.
Get subscription plan pricing and sign up for OnStar Vehicle Diagnos ...
Storing a Radio Station as a Favorite
To store a station as a favorite:
1. Tune to a radio station.
2. Press the FAV button to display the page where the station will be stored.
3. Press and hold one of the six softkeys until a beep so ...
Finding a Category (CAT) Station
CAT (Category): The CAT button is used to find XM stations when the radio is in the XM mode.
To find XM channels within a desired category:
1. Press BAND until the XM frequency displays.
2. Press C ...