With the full-size GMC Sierra and Chevrolet Silverado pickups that GM introduced this past year, the company gave more of a heavy-duty look to those light-duty models—as well as some stepped-up capability. Now it's essentially leapfrogging with its true HD trucks, grabbing that more chiseled, refined appearance, and making the HD trucks even bolder, even more refined-looking.
The new HD lineup includes both 2500HD and 3500HD models, with what GM says are segment-leading capabilities across the model range. Among these models, there's the highest payload among heavy-duty trucks—7,374 pounds—as well as the highest conventional trailering rating, of 19,600 pounds.
Gas or diesel V-8s, six-speed automatics
Under the hood (which, by the way, is aluminum in all of GM's new HD trucks), you have a choice between two strong V-8 engines: a 6.0-liter gasoline engine, making 360 horsepower and 380 pound-feet, or a stout 6.6-liter Duramax diesel, making 397 hp and 765 lb-ft. The gasoline engine is E85-compatible, and mated to a six-speed Hydra-Matic automatic transmission, while the diesel gets an Allison 1000 six-speed automatic. Two different final drive ratios are offered for the gasoline models—4.10 or 3.73—while all diesel models have the latter.
That said, those powertrains are essentially carried over for this refresh, as are the majority of the HD's underpinnings. All models include four-wheel disc brakes with four-wheel anti-lock braking, as well as a long- and short-arm torsion-bar front suspension and leaf springs in back, as well as sturdy recirculating-ball steering (as opposed to the rack-and-pinion unit in light-duty models).
More handsome look, better aerodynamics
Just as in the light-duty Sierra 1500, new inlaid doors fit into body-side recesses, helping to reduce wind noise and result in a quieter interior—as well as improved aerodynamics. Stronger structural B-pillars enhance solidity; crew cab models have longer rear doors, and in double cab models you can open the rear doors without opening the front ones.
Two box lengths will be offered—6'6” and 8'—both with a two-tier loading design with more than four feet between the wheel houses (good for 4x8 plywood).
GM has brought a number of features from the Sierra 1500 and Silverado 1500 right over to the Sierra and Silverado HD trucks—including the CornerStep rear bumper and damped, EZ Lift and Lower tailgate.
Even the 3500HD dually has electronic stability control with Trailer Sway Control, while the integrated cruise control includes auto grade braking and diesel exhaust braking, to help increase safety and reduce brake wear.
Interior upgrades—yes, including MyLink and IntelliLink
GMC Sierra HD models get a somewhat better feature set than Silverado HD models—including a top-of-the-line Denali trim some luxury-caliber interior and feature upgrades. But prices remain a bit higher.
The look and feel of the instrument panel has been improved along the lines of the 1500 trucks. But the most noteworthy thing might be that these HD trucks get the newest version of MyLink (Chevy) and IntelliLink (GMC), the brands' infotainment system that combines a touch screen, voice commands, and connectivity with smartphones and other devices, for hands-free calling and media access. Here it includes a reconfigurable eight-inch screen, and up to five USB ports, four 12-volt outlets, a 110-volt outlet, and an SD card slot.
The new HD trucks will hit the market in the first quarter of 2014.