General Motors has launched its 2011 Chevrolet Silverado HD and GMC Sierra HD with aims of winning the heavy-duty power battle. ENR accepted GM’s invitation to test and compare its re-engineered trucks against the competition, namely the 2011 Ford Super Duty that we reviewed in the spring.

Nuts and Bolts

GM has beefed up the two available powertrains in its 2011 offerings to handle heavier loads. Starting things off is the 6.0-liter V-8, good for 360 horsepower and 380 lb-ft of torque. Impressive, but GM’s Duramax turbodiesel—a 6.6-liter V-8— delivers 397 horsepower and 765 lb-ft of torque, and packs a heavier punch. Mileage is estimated to reach roughly 19 mpg while running on diesel fuel (the Duramax is also B20 compatible), with a urea-based Diesel Exhaust Fluid (DEF) system to address stringent air-quality standards.

These changes mean a more capable rig that tows up to 21,700 lb and carries a payload of 6,635 lb. With the exception of Ford’s F-450, that puts GM at the top of the heavy-hauling chart. The Duramax comes with an upgraded Allison six-speed automatic gearbox.

New features like redesigned hoods and bumpers distinguish these trucks from their predecessors. More important features are the wider leaf springs; a redesigned front suspension that allows four-wheel-drive models to accommodate a snow plow; a stronger fully boxed frame; and trailer sway control and StabiliTrak, standard on all single-rear-wheel variants.

Like its competitors, GM is now offering exhaust braking with its diesel engine. But its cruise control integration system, which allows drivers to simply set the speed and let the powertrain do all the braking on down grades, makes it unique. Engineers have also improved GM’s Heavy Duty rides with a trailer brake controller, intelligent brake assist and hill-start assist.

What you won’t find on the 2011 trucks is the breadth of fleet management technology offered by Ford’s Work Solutions option, but GM buyers can get Autonet Mobile, a Wi-Fi setup that grants Internet access to 10 computers within 150 feet.

Behind the Wheel

The duo of GM heavy duty trucks are arguably the most hospitable heavy duty rigs, thanks to spacious and well-contoured front seats. The rear bench in Crew Cab variants is a good place to park your backside, though legroom is three inches shorter than the Ford Super Duty.

We tested the 6.0-liter V-8 with a payload of about 1,800 lb, and while that weight was noticed, the engine didn’t feel taxed. A short jaunt in an unladen Regular Cab Work Truck rewarded us with quick acceleration and smooth shifts.

When towing about 10,000 lb of trailer and Bobcat equipment, the Duramax diesel truly shines. With 765 lb-ft of torque available at only 1,600 rpm, pulling power wasn’t an issue, while upsized rotors and the exhaust brake provide confident stopping capability. Yet, even with less output, Ford’s Power Stroke delivers more immediate punch and, as a result, is more responsive.

Loaded or unloaded, the trucks offer superior steering feel and relatively stress-free heavy towing at highway speeds, even with blustery crosswinds.

Look Past Exterior

If big power and capability rule the heavy-duty roost, look no further than GM’s 2011 three-quarter and one-ton trucks, priced from $27,965, with the Duramax/Allison combo adding $8,395 to the bottom line. Don’t be misled by the seemingly unchanged exterior—these vehicles are all-new where it counts.