We all like big trucks in way that few people can explain. May be it is because of all that brutal power, angular lines or just because "it is big". GMC has unveiled the Sierra All Terrain HD Concept, which will has its debut at the NAIAS.

The vehicle boasts custom control arms, Fox off-road shocks, front and rear jounce shocks, automatic locking differentials, and a beefy front stabilizer bar with electric disconnection. It is designed to be the ultimate off-roader, so Sierra All Terrain HD is shorter, wider, and taller compared to a standard model.

The big truck stands on enormous 35"BFGoodrich KM2 tires fitted on 20" aluminum wheels. It also has a a massive grille, bulging fender flares and LED lights, of course. More important are the air compressor and a 110-volt outlet.

The interior boasts two-tone leather seats, satin chrome trim, and a next-generation navigation system with an 80 GB hard drive.

The engine of this monster is 6.6 liter Duramax V8 diesel with 397HP (296 kW) and staggering 1 037 Nm (765 lb-ft) of torque, which is enough to tow a mountain. Still, the towing capacity is limited to ~ 5.9 tons ( 13 000 pounds) and if it is not enough, the vehicle offers a a payload capacity of 1 225 kg (2700 pounds).

GMC Sierra All Terrain HD Concept, 1 of 12
GMC Sierra All Terrain HD Concept, 2 of 12
GMC Sierra All Terrain HD Concept, 3 of 12
GMC Sierra All Terrain HD Concept, 4 of 12
GMC Sierra All Terrain HD Concept, 5 of 12
GMC Sierra All Terrain HD Concept, 6 of 12
GMC Sierra All Terrain HD Concept, 7 of 12
GMC Sierra All Terrain HD Concept, 8 of 12
GMC Sierra All Terrain HD Concept, 9 of 12
GMC Sierra All Terrain HD Concept, 10 of 12
GMC Sierra All Terrain HD Concept, 11 of 12
GMC Sierra All Terrain HD Concept, 12 of 12