By Tim Healey
Forget the pony-car wars. Ford, GM, and Chrysler are engaged in yet another arms race--this one revolving around heavy-duty pickup trucks. Dodge and Ford have already updated their heavy-duty trucks in recent months, and now it's General Motor's turn. Despite downturns in the heavy-duty truck market due to the economic collapse, these trucks still appeal to a very specific segment of buyers. The Detroit automakers dominate this segment, and much like Cold War-era superpowers, the three keep raising the stakes in the big-truck game.
Capability usually trumps styling with vehicles like these, and to that end, the 2011 Chevrolet Silverado HD and 2011 GMC Sierra HD don't get a lot of styling changes, save for a new grille, front bumper, and hood, to go along with some new wheel choices.
What has changed, as the GM folks made clear during their presentation to the media, is what's under the sheetmetal. The engines, transmissions, and chassis are all either new or re-worked. There's also a new independent front suspension, which is said to increase the front-axle rating by 25 percent over the previous generation.
Truck buyers invariably ask "what's under the hood?" and in this case, it's either a 6.0-liter Vortec gasoline V-8 or a new 6.6-liter Duramax diesel. The diesel makes 397 horsepower and 765 lb-ft of torque, while the gas engine makes 360 horsepower and 380 lb-ft of torque.
As powerful as the gas engine is, the focus here is on the oil-burner, and not just because of the eye-popping torque rating. The new Allison 6-speed automatic transmission that matches to the diesel gets some attention, mainly because of its "smart" exhaust brake.
For those uninitiated in the lingo of these heavy-haulers, the exhaust brake uses a variable geometry turbocharger in concert with the engine's compression, to create backpressure, thus slowing the truck without use of the regular brakes. In practice, the idea is for the exhaust brake to work with the cruise control and the "tow/haul" mode of the transmission to slow the truck, therefore hopefully reducing wear on the brake pads.
Other available features of note include a hill-start assist, park assist, navigation system, OnStar, USB compatibility, Bluetooth, and satellite radio. Mobile Wi-Fi is also available.The biggest news is that for the first time, a Denali version of the heavy-duty Sierra will be available. Not only that, but the Denali will be available in both 2500 (three-quarter ton) and 3500 (one-ton) guise. Denalis will be available with either engine, with either two- or four-wheel drive, and with dual-rear wheel (dually) set-ups. 3500 Denalis will be available with either a 6-foot,, 6-inch bed or an 8-foot bed.
Denalis are differentiated by their four-bar chrome grilles, body-color bumpers, chrome door handles, chrome accents, upscale interiors, and 18-inch standard wheels (17-inch on duallys). 20-inch wheels are available.
The brakes consist of 14-inch rotors, and GM's Stabilitrak system is standard on trucks with single rear wheels.