Used 2012 GMC Sierra 2500HD

With its considerable capabilities and comfortable nature, the 2012 GMC Sierra 2500HD is an excellent choice for a heavy-duty truck.

In the General Motors family, GMC is positioned as the truck division. And although GMC Sierras are essentially twins under the skin with their Chevrolet Silverado relatives, GMC's pickups are nonetheless heavy hitters. The 2012 GMC Sierra 2500HD in particular is a slugger among some very tough competitors.

Although it might not look as if the Sierra has changed much since 2007, it has been upgraded steadily over the years. Last year brought a number of substantial improvements that included a stronger, fully boxed frame, a revised suspension, a more powerful turbodiesel engine (an option) and a new Allison transmission. They all added up to a more comfortable ride, better performance and handling dynamics and higher hauling/towing capacities. Speaking of the turbodiesel, it's rated at an impressive 397 horsepower and 765 pound-feet of torque, which of course translates into serious work potential that includes a maximum towing capacity approaching 17,000 pounds.

Put wheel-to-wheel against its rivals, the 2012 GMC Sierra 2500HD (and Chevy Silverado twin) can't quite match the Ford F-250 Super Duty in terms of all-out hauling and towing capacities, nor match the Ram 2500 in terms of upscale cabin ambience (in lower trim levels, anyway). But the GMC boasts the best all-around performance and feels the most composed while towing a very heavy load, thanks to its more precise steering and arrow-straight tracking. But none of these heavy-duty pickups represents a clear winner or loser, and realistically your choice could come down to styling preference or brand allegiance.

The 2012 GMC Sierra 2500HD is offered in regular cab, extended cab or crew cab body styles. The regular cab is only available with a long bed (8 feet), while the extended and crew cabs also can be had in standard bed lengths (6.5 feet). Trim levels start at the base Work Truck and climb to the SLE, SLT and range-topping Denali.

The Work Truck trim level includes 17-inch steel wheels, air-conditioning, cruise control, a trip computer, rubber floor coverings, a 40/20/40-split front bench with fold-down center armrest, vinyl upholstery, a tilt steering wheel and a four-speaker AM/FM stereo.

Stepping up to the SLE adds alloy wheels, tinted rear windows, keyless entry, full power accessories, carpeted floor coverings, cloth seats, a leather-wrapped steering wheel, driver-side lumbar adjustments, OnStar, satellite radio and a CD/MP3 player. Many of the SLE features are available on the Work Truck as options.

The SLT trim level is only offered on extended and crew cab body styles and augments the SLE's features list by adding 18-inch alloy wheels, foglights, a locking rear differential, a heavy-duty trailering package (with integrated trailer brake controller), heated exterior mirrors, dual-zone automatic climate control, an auto-dimming rearview mirror, steering-wheel-mounted cruise and audio controls, remote starting, heated leather front bucket seats with power adjustments, a front center console, Bluetooth and an upgraded Bose stereo system with a USB port. Some of these features are available as options for the SLE.

On top of the SLT features, the Denali will get you a four-bar chrome grille, chrome exterior accents, rear parking sensors, the EZ-lift tailgate, skid plates, power-adjustable pedals, heated/ventilated front seats and brushed metallic trim. Many of these features are available on lower trim levels as options.

Additional options are dependent on trim level and include 20-inch wheels, an aluminum bed extender, a protective bedliner, a sliding or stationary tool box, a cargo rail, a sliding bed divider, a sunroof, power-sliding rear window, a heated steering wheel, a hard-drive-based navigation system, mobile WiFi, a rear-seat DVD entertainment system and a rearview camera. Four-wheel-drive models can add the Z71 off-road package (includes skid plates and off-road suspension components) and a Snow Plow Prep package.

The standard power plant for the 2012 GMC Sierra 2500HD is a 6.0-liter V8 engine that produces 360 hp and 380 lb-ft of torque. A six-speed automatic is the only available transmission. An optional 6.6-liter turbodiesel V8 is the engine of choice for those who plan on towing or hauling on a regular basis. This "Duramax" turbodiesel produces 397 hp and 765 lb-ft of torque and is mated to a beefier six-speed automatic transmission with manual shift control. In Edmunds performance testing, a Sierra 2500HD with this engine accelerated from zero to 60 mph in a truly extraordinary 7 seconds, which is 2 seconds quicker than the Ram 2500HD.

The Duramax is a clean diesel, thanks in part to a urea-injection system. If the diesel exhaust fluid (DEF) runs low, however, top speed will be limited to 55 mph. If the DEF reservoir is empty, that speed is lowered to 40 mph.

Rear-wheel drive is standard for all models, with four-wheel drive optional. The Work Truck 4WD has a traditional floor-mounted transfer case, while the other trim levels get Autotrac, a knob-controlled electric transfer case that features an automatic setting that engages 4WD when wheel slippage is detected.

Properly equipped, a 2012 GMC Sierra 2500HD can haul up to 3,704 pounds of payload and tow up to 13,000 pounds with its standard ball hitch, and 17,800 pounds with a fifth-wheel connection. Aiding trailering on downhill grades, the diesel engine also features a big-rig-inspired exhaust braking system to increase control and reduce brake wear.

The 2012 GMC Sierra 2500HD features antilock disc brakes, stability control, hill-start control and trailer sway control as standard. Front side and side curtain airbags are available as an option. Power-adjustable pedals and rear parking sensors are standard on the Denali (optional on others) and a rearview camera is available for all models.

In Edmunds brake testing, a 2500HD Denali came to a stop from 60 mph in 144 feet, which is long, but common for a heavy-duty truck.

The 2012 GMC Sierra 2500HD manages to provide a comfortable ride along with its strong work capacity thanks to its stiff frame and a suspension that can not only handle higher loads but also smooth out rough roads.

When stacked up against the Ford F-250 and the Ram 2500, the GMC 2500 has a few clear advantages. Superior steering precision compared to the Ford and a smaller turning circle than either rival are readily apparent and appreciated in everyday driving. And when towing a trailer, the Duramax turbodiesel accelerates with more authority and climbs grades with less diesel clatter while also delivering superior fuel economy. When descending a grade, the Duramax's exhaust brake works with well-timed downshifts from the transmission to lend an edge in vehicle stability over the Ram.

As expected, the Work Truck has the most utilitarian interior of the lineup with vinyl seats, rubber floor covering and very little in the way of creature comforts. The SLE offers a more inviting cabin with cloth seats and carpeting, but both models come standard with a three-person front bench that requires a more trucklike dash. Opting for the bucket seats will add a center console with storage. The SLT and Denali are the classiest of the bunch, with an interior similar to that of the Yukon SUV.

The front seats are quite comfortable, though some drivers might find the driving position a bit awkward because of the tilt-only steering wheel (it's too close to the dash) and gas and brake pedals that are far apart in order to accommodate work boots. We're also not particularly fond of the small and finicky buttons on the higher trim's center stack.

The extended cab's rear fold-up seats are acceptable in terms of comfort but more suited for children. On the plus side, the extended cab's rear doors swing out 170 degrees to aid with loading the backseat area in tight spaces. The crew cab also features a fold-up rear seat and is much roomier, but falls short on most dimensions when compared with the competition.