ST LOUIS -- General Motors has boosted the payload, towing and power of the 2011 GMC 2011 Sierra heavy-duty 2500 and 3500 pickups and chassis cab models.
And GMC is introducing the first Denali model to its heavy-duty pickup line.
The trucks debut today at the National Truck Equipment Association’s Work Truck Show in St. Louis.
“The new Sierra Denali HD is the latest expression of GMC’s Denali philosophy of blending capability with premium features and styling,” Lisa Hutchinson, GMC product marketing director, said in a statement.
At the show, GM also announced the horsepower and torque of the re-engineered 6.6-liter turbocharged Duramax diesel: 397 hp at 3,000 rpm and 765 pounds-feet of torque at 1,600 rpm. The previous engine generated 365 hp and 660 pounds feet of torque.
Last year GMC sold 111,842 full-sized pickup trucks -- a 34 percent decline from 2008. Among the 2009 sales, about a third were heavy-duty models. The Sierra and 2011 Chevrolet Silverado heavy-duty models go on sale this summer.
The Sierra Denali will be available only on the 2500 heavy-duty chassis equipped with four-wheel drive and the crew cab, standard box configuration. GM’s Vortec 6.0-liter V-8 is standard and teamed with a six-speed automatic transmission. The turbocharged 6.6-liter Duramax diesel engine and Allison 1000 six-speed transmission powertrain are optional.
The Denali’s exterior is distinguished by a four-bar, chrome grille with round air inlets; body-color bumpers; chrome door handles; chrome accents; and polished forged aluminum wheels.
Non-Denali models have a new three-bar grille and louvered hood, along with a restyled chrome steel front bumper and a new family of 17-, 18- and 20-inch wheels.
Under the skin, General Motors says the 2011 GMC Sierra 2500 and 3500 heavy-duty pickups have been extensively re-engineered. Among the highlights:
New frames that GM says are five times stiffer torsionally and 92 percent stiffer in the bending mode.
Increased towing capability of up to 20,000 pounds and payload capacity of 6,335 pounds.
A new front suspension re-engineered to handle a 25 percent greater axle rate rating, up to 6,000 pounds.
A larger asymmetrical leaf-spring design in the rear suspension to handle increased payload capacity
Larger front and rear brakes.
A new feature is the hill-start assist system, which engages the brakes when the vehicle is on a grade of 5 percent or greater. The system holds the brakes for 1.5 seconds or until the gas pedal is pressed, preventing rollback. Stability control is standard on single, rear-wheel drive models.
GMC and Chevrolet 3500 heavy-duty chassis cab models receive similar improvements: The gross vehicle weight rating is boosted to 13,200 pounds. Additionally, the gross combined weight rating on models with dual rear tires is increased to 27,500 pounds.
Sales begin this summer, along with commercial 2500 and 3500 heavy-duty, box-delete models.
Box-delete models now are offered in a crew cab configuration. The crew cab replaces the previous extended cab.