What is it? Like the Ford Raptor and Dodge Ram Power Wagon, the GMC Sierra All Terrain HD combines a heavy-duty truck with off-road capabilities. It underpins the All Terrain HD concept with some modificationsa raised 4WD chassis and the 6.6-liter Duramax diesel V8 with Allison 1000 six-speed transmission combined to put out 397 hp.
Height has been increased three inches to provide better clearance and features a wider 73-inch track, but it is shorter in length than production Sierra HD models. Chunky 20-inch wheels are wrapped in 35-inch tall tires and Fox off-road shocks help performance on rough terrain. Payload capacity is 2,700 lbs and towing capacity 13,000 lbs.
Inside is a new navigation radio with an 80-gig hard drive and map data for navigation. It also has a time lapse playback similar to a DVR that allows you to play back music from traditional radio or satellite.