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:
Additional Program Information
All program options, such as shuttle service, may not be available at every dealer.
Please contact your dealer for specific information about availability. All Courtesy
Transportation arrangements ...
Adding Destinations to the Address Book
There are two ways to add a destination to the address book:
To add the current vehicle position to the address book, press the Mark
screen button from the map screen. The system automatically ...
Diagnostics
OnStar Vehicle Diagnostics will perform a vehicle check every month. It will
check the engine, transmission, antilock brakes, and major vehicle systems.
It also checks the tire pressures, if the v ...