See also:

Warranty
OnStar equipment may be warranted as part of the new-vehicle limited warranty. The manufacturer of the vehicle furnishes detailed warranty information. ...

Navigation
OnStar navigation requires the Directions and Connections service plan. Push to receive directions or have them sent to the vehicle navigation screen. Destinations can also be forwarded to the v ...

Powertrain details
The GMC Sierra All Terrain HD concept is propelled by the new, production 6.6L Duramax turbo-diesel V-8 and Allison 1000 six-speed automatic transmission powertrain combination offered in the 2011 ...