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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 ...

Using this Manual
To quickly locate information about the vehicle, use the Index in the back of the manual. It is an alphabetical list of what is in the manual and the page number where it can be found. ...

Sunroof
The ignition must be in ON/RUN or ACC/ACCESSORY to operate the sunroof and power sunshade. See Retained Accessory Power (RAP) on page 9‑20. The vehicle may have a sunroof over the front seats ...