Vehicle Overview
While mechanically identical to the Chevrolet Silverado heavy-duty models, GMC positions the Sierra 2500HD/3500HD to appeal to a more upscale customer. There's a little more flash on the outside and a little more elegance on the inside. But the real selling point for the Sierra is the same as the Silverado: the combination of a Duramax diesel and Allison six-speed automatic transmission.

Trims for the Sierra 2500 heavy-duty trucks include Work Truck, SLE and SLT. All HD trucks can be ordered in two- or four-wheel drive. The standard powertrain is a 6.0-liter gas engine and six-speed Hydra-Matic automatic transmission, while the diesel is optional. GM says the 2500HD and 3500HD can tow up to 13,000 pounds with the diesel engine and a conventional hitch. The maximum towing capacity with a fifth-wheel hitch is 16,700 pounds; payload varies between 2,331 pounds and 5,309 pounds, depending on the model.


New for 2010
There are no significant changes for 2010.

Exterior
The Sierra heavy-duty trucks are visually distinct from their Chevy cousins and Sierra 1500 models. The grille opening is more pronounced, and the headlamps and hood are different. Even the dually has integrated, hydroformed steel fenders. Fog lamps on the SLT models are set into the bumper for an upscale appearance.

Exterior features include:
  • Available moonroof on extended and crew cabs
  • Available EZ Lift tailgate
  • Tow mirrors available
  • Side, roof markers on dually models


Interior
The GMC interior themes found on the Sierra 1500 carry over to the heavy-duty models. The Work Truck and SLE trims feature more work details, while the SLT is more luxurious. The most obvious difference is the dash design. The Work Truck has a double glove box and the SLT has a single glove box. The Work Truck has armrest storage built into the 40/20/40-split bench seat, and there's also a lockable storage bin large enough for a laptop under the center-seat section. GMC offers a wide range of audio options with a Bose sound system available in premium models.
  • Available rear-seat DVD player
  • Power-adjustable foot pedals
  • Available power rear window on extended and crew cabs
  • Stadium-style seating in second row


Under the Hood
  • 360-horsepower, 6.0-liter V-8, with iron block and aluminum cylinder head, cam-in-block, two valves per cylinder, making 380 pounds-feet of peak torque mated to a six-speed Hydra-Matic automatic transmission
  • 365-hp, 6.6-liter V-8 diesel, with iron block and aluminum cylinder head, cam-in-block, four valves per cylinder, making 660 pounds-feet of peak torque mated to a six-speed Allison automatic transmission


Safety
GM's electronic stability control system, StabiliTrak, is available on select 2500HD models. Side-impact and side curtain airbags are not available. Other safety features include:
  • Dual front airbags standard
  • Ultrasonic rear parking assist available
  • Four-wheel antilock brakes