See also:

New for 2011
The Sierra Hybrid gets GM's OnStar 9.0 telematics system that GM says provides better voice recognition. GM also said they have worked to cut down on the amount of wind noise occupants hear. ...

OnStar®
If equipped, this vehicle has a comprehensive, in-vehicle system that can connect to a live Advisor for Emergency, Security, Navigation, Connection, and Diagnostic Services. See OnStar Overview on pag ...

Under the Hood
Mechanical features include: 185-horsepower, 2.9-liter inline-four-cylinder with aluminum block and cylinder head, dual overhead camshafts and four valves per cylinder that makes 190 pounds-feet ...