GMC unveiled the all-rounders in Sierra HD Concept, referred to as the exploration of the ability of heavy trucks in combination with the versatile off-road, highlighted by a bold exterior design. The new HD 2011, Sierra also underlies the entire concept of high definition field, with an amendment, based on the production of the unit 4-wheel chassis Duramax diesel / driveline six-speed Allison 1000.
The Sierra All Terrain HD Concept features a unique five-foot, eight-inch Crew Cab/short box body configuration that supports a wheels-at-the-corners proportion. Shorter in overall length than production Sierra HD models, the concept features enhanced suspension and unique body dimensions, including increased ground clearance and wider track, as well as greater approach/departure angles to deliver off-road capability.
The 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 power-train combination offered in the 2011 Sierra HD trucks. The Duramax is rated at 397 horsepower (296 kW) and 765 lb.-ft. of torque (1,037 Nm). The 6.6L Duramax is more fuel-efficient – with up to 11% greater fuel economy than previous versions – and reduces NOx emissions by up to 63%.
With the same proven power-train as production Sierra HD trucks, the All Terrain HD delivers comparable hauling and towing capabilities, including: est. payload capacity of 2,700 pounds (1,225 kg), est. conventional towing capacity of 13,000 pounds (5,896 kg), and est. fifth-wheel towing capacity of 15,600 pounds (7,076 kg).
The Sierra All Terrain HD also features four-wheel drive, with automatic locking front and rear differentials, while the 14-inch, four-wheel disc brake system from the production Sierra HD provides the stopping power for this unique off-roader.