2013 GMC Sierra 3500HD Denali

The GMC Sierra 3500HD Denali is something of a rolling contradiction. As with the Sierra 3500HD upon which it is based, it is the largest, sturdiest, most work ready-truck that General Motors offers. However, it is also what construction workers might refer to as a city-slicker's truck, complete with a leather and wood trimmed interior, copious amounts of chrome, and unique 18-inch aluminum wheels. It is not exactly ideal to step into with muddy clothes or to use to ford a river.

The 3500HD Denali comes standard with a gas-powered V8, while a turbodiesel eight-cylinder is optional. The gas-burning 6.0 V8 puts out 360 horsepower and 380 lb-ft. of torque, while the mighty diesel displaces 6.6 liters and makes a staggering 397 horsepower and 765 lb-ft. at a usefully low 1,600 rpm. Both engines put their power to the ground via 6-speed automatic transmissions, though the diesel uses a heavy-duty Allison unit.

Maximum payload and towing capacity are up for the latest model year to 7,215 and 18,000 pounds, respectively, although those numbers change depending on engine, drive wheels and length. The increases are due to a variety of enhancements, including beefier rear springs and U-bolts, revised rear axle tubes and shock tuning, revised pickup box cross sills and other structural enhancements, modified box mounting on the frame and a revised trailer hitch receiver.

Several features work together to make carrying and towing such heavy loads easier. A trailer-sway control system senses conditions of trailer sway and automatically intervenes with braking and/or reduced engine power to bring the trailer under control and keep its on its intended path. A hill start assist system engages when sensors detect the vehicle is on a grade of about 5 percent or greater, holding the brakes for 1.5 seconds or until the gas pedal is pressed in order to prevent rollback.

Finally, an exhaust brake, standard with the turbodiesel, uses the turbine control of the variable geometry turbocharger in addition to the compression of the engine to generate backpressure, slowing the vehicle without the driver applying the brakes. This helps to prolong brake life and prevent overheating on long, downhill grades.

The 3500HD Denali is available with a 78.8-in. standard bed with single rear wheels or as a dualie with a 97.7-in. long bed, but comes only as a four door extended cab. Rear- or four-wheel drive is available.

Outside, the 3500HD Denali distinguishes itself with a four bar chrome grille with round air inlets, body-color bumpers, chrome door handles, chrome accents and standard 18-inch polished forged aluminum wheels that would be a shame to scrape up on an off-road trail.

Leather seats with 12-way power adjustment, brushed aluminum trim and power adjustable pedals make the interior a comfortable place to relax on the way home from the construction site, although on average the grade of interior plastics is disappointing for the price. For the latest model year, heated and cooled seats and a leather wrapped, heated steering wheel are standard, as is a rear-view camera that makes parking the big rig a bit easier.

Significant options include a touch-screen navigation system bundled with a 7 speaker Bose audio system, an off road package with skid plates and beefy shock absorbers and a rearview camera system.

Those in northern climates might consider the available heated (and cooled) seats and heated steering wheel.

Occupant Safety
Standard safety features include dual front, front side and side curtain airbags in addition to traction and stability control systems and a tire-pressure monitoring system.

Key Competitors
In this class, only the Ford F-350 King Ranch can compete with the level of luxury offered by the Sierra 2500HD Denali. While the leviathan Ford ultimately has higher towing and payload capacities, the GMC 's slightly smaller size and curb weight can make it a more user-friendly truck in all but the most intense work situations.

The slightly less luxurious Ram 3500 with the Laramie Longhorn trim level could also be considered a rival.