See also:

Roadside Assistance Program (U.S. and Canada)
For U.S.-purchased vehicles, call 1-888-881-3302; (Text Telephone (TTY): 1-888-889-2438). For Canadian-purchased vehicles, call 1-800-268-6800. Service is available 24 hours a day, 365 days a year. ...

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 ...

Under the Hood
GM's two-mode hybrid system enables "full" hybrid operation with the capability to cruise on electric power up to 30 mph. The gas engine kicks in if more acceleration is needed, as well ...