In the same way that Ford’s F-Series of trucks includes both the regular full-size F-150 pickup truck range and the bigger Super Duty variants, GM’s Chevrolet and GMC brand’s offer both standard and larger heavy duty versions of their Silverado and Sierra pickup trucks respectively.

Following on from last year’s introduction of the new generation 2014 Chevrolet Silverado and GMC Sierra trucks, today, GM revealed the 2015 Heavy Duty (HD) bodies of the two models, appropriately, at the State Fair of Texas.

As is the case with most common models between the Chevrolet and GMC brands, the Sierra HD is the slightly more luxurious and better looking vehicle of the two, though, most parts are shared. In addition to the regular Sierra HD models, GMC also offers a more distinct looking and even better equipped Denali grade with a unique chrome grille, special interior trim, an 8-inch customizable driver display and more.

Both the Silverado HD and Sierra HD will come as standard with a Vortec 6.0-liter gasoline V8 developing 322HP and 380 lb-ft (515Nm) in the 2500 HD models, and 360HP and 380 lb-ft (515Nm) in the 3500HD bodies, linked to a Hydra-Matic six-speed automatic. A bi-fuel version of the 6.0-liter V8 for operation on gas or compressed natural gas will also be available.

Those looking for more power on either model will find a 6.6-liter Duramax V8 turbo-charged diesel rated for 397HP and 765 lb-ft (1,037Nm) of peak torque paired to an Allison 1000 6-speed auto.

Maximum payload for the 2500HD models is 4,306 pounds (1,953 kg) and for the 3500HD, 7,374 lbs (3,508kg), while maximum conventional trailing, 14,500 lbs (6,577 kg) and 19,600 lbs (8,890 kg) respectively.

Sales of all models in the States will begin in the first quarter of 2014.

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