If you want a heavy-duty pickup, the options are limited. The Big Three American manufacturers are the only players in this segment, and to the casual observer, their respective entrants may appear to be mere variations on a theme. There are significant differences among these workaday behemoths, though, as the 2009 GMC Sierra 2500HD demonstrates. Having received the most recent redesign in its class, it's an up-to-date truck, and its superior driving dynamics and extraordinary interior quality nicely complement its expected hauling and towing talents.

The 2009 Sierra 2500HD receives a handful of useful upgrades, including a new version of OnStar, available stability control and Bluetooth connectivity. The rest of the truck remains unchanged from its complete overhaul two years ago, which brought fresh styling, a dramatically improved interior, better handling, a more powerful engine lineup, a stronger frame and higher payload and towing capacities. As ever, this is a truck that will get the job done. Thanks to these changes, it will also keep you comfortable while doing it.

Whether you opt for the Sierra 2500HD or its Chevrolet Silverado 2500HD twin, you can't go wrong with these well-mannered brutes. The Ford F-250 is its closest competitor, but the GM trucks are a bit more capable, and they arguably offer a nicer interior, particularly in the SLT trim. The Dodge Ram 2500 nearly matches the Sierra's towing capacity and ride comfort, but it is getting along in years and will soon be replaced by an all-new model. It also can't match the GMC's cargo bed configurations or interior quality. That leaves the 2009 GMC Sierra 2500HD as your best bet. Along with its Silverado sibling, it rules the roost -- for now -- in this hard-working segment.

The 2009 GMC Sierra 2500HD full-size heavy-duty pickup is available in three body styles: regular cab, extended cab and crew cab. Regular cabs come with a long bed, while extended cabs and crew cabs can have either a standard or long bed. Regular cabs are offered in base Work Truck (WT) or midlevel SLE trims; extended and crew cabs can also be had in plush SLT form.

The WT trim comes standard with air-conditioning (optional with the regular cab), a trip computer, a CD player, satellite radio, OnStar, vinyl seating, a 40/20/40-split front bench seat and a tilt steering wheel.

The SLE trim adds deep-tinted windows, chrome-style steel wheels, cruise control, full power accessories, heated exterior mirrors, dual-zone automatic climate control, cloth seating, keyless entry and a leather-wrapped steering wheel.

The top-of-the-line SLT is only available with the extended and crew cabs. It adds a locking rear differential, a heavy-duty trailering package (with an integrated trailer brake controller), remote engine start, an upgraded dash design, a Bose audio system with a six-CD changer and rear audio controls, 12-way power-adjustable heated front bucket seats and leather upholstery.

Options, depending on truck configuration, include a back-up camera, a power-sliding rear window, a navigation system with available real-time traffic, a rear-seat DVD entertainment system, rear park assist, a sunroof, camper-style side mirrors, the Z71 Off-Road package (including skid plates, off-road suspension and a locking rear differential), a safety package (including power-adjustable pedals and park assist), a cargo management system and an "EZ lift" tailgate.

A 6.0-liter V8 generating 353 horsepower and 373 pound-feet of torque is standard on all Sierra 2500HD trucks, as is a six-speed automatic transmission. Optional is a burly Duramax 6.6-liter turbodiesel V8, which boasts 365 hp and a space-time-continuum-wrenching 660 lb-ft of torque. The turbodiesel comes paired with an Allison six-speed automatic. Properly equipped, the 2500HD can haul up to 3,458 pounds and tow up to 13,000 pounds.

Buyers have a choice of either rear- or four-wheel drive. A WT with 4WD has a traditional floor-mounted selector for the transfer case. The two other 4WD trims have Autotrac, which features an automatic setting that shifts into 4WD when wheel slippage is detected.

Antilock disc brakes are standard, but front side and side curtain airbags are not available. Stability control is standard on extended- and crew-cab models with single rear wheels but is unavailable on all other models.

Compared with the heavy-duty trucks from Ford and Dodge, the 2009 GMC Sierra 2500HD distinguishes itself with well-weighted steering that gives the driver a greater sense of vehicle control. Heavy-duty pickups are never going to ride like luxury sedans, but the 2500 is surprisingly quiet and comfortable over long distances. Both engines are strong, but if you can swing the price premium, the brawny performance and decent fuel economy of the Duramax diesel make it a tempting choice.

The 2009 GMC Sierra 2500HD features two different interior designs depending on trim level. The WT and the SLE sport a traditionally trucky dash design with an open lower center portion to accommodate the standard three-person front bench (a center console is added with the optional bucket seats). Conversely, the top-of-the-line SLT gets the same layout as the GMC Yukon SLT SUV, which lends the Sierra's cabin a classier feel, thanks to its luxury-carlike center stack design, high-quality materials and wood and metallic accents. Either way, the controls are straightforward and relatively easy to reach, though the available dual-zone climate controls are small and difficult to operate with gloves.

The front seats are quite comfy, though some editors found the pedals placed too far apart for comfort. Moreover, the tilt-only steering wheel is located too close to the dash for longer-legged operators. Space in the crew cab's backseat is plentiful, while most average-size adults should find the extended-cab's backseat acceptable. A welcome addition for 2009 is the optional rearview camera for extended- and crew-cab models, which makes parking easier and also streamlines the process of hitching up a trailer.