Chevrolet Bows New 2011 Silverado HD Full-Size Truck at Chicago Auto Show

Boasting a completely new chassis and updated mechanical hardware, the new 2011 Chevrolet Silverado made its official debut today at the Chicago Auto Show. And if it looks no different than the 2010MY, that's because General Motors focused its attention on what matters most for work trucks the chassis and engine lineup resulting in improved payload and trailer capability as well as better fuel economy.

The most significant change to the 2011 Silverado is the all-new, fully-boxed frame assembly. GM says that the bending and beaming stiffness of the frame is increased 92 percent and 20 percent, respectively, with the fully boxed sections enhancing torsional stiffness by a factor of five.

There's also a redesigned independent front suspension system that offers up to a 25-percent greater front axle weight rating – up to 6,000 pounds (2,721 kg) front gross axle weight rating (FGAWR), while at the back, there's new, larger asymmetrical leaf-spring design.

The standard four-wheel disc system has also been upgraded with a set of larger 14-inch front and rear rotors while Duramax-equipped models now get a new exhaust brake system.

Under the hood, GM re-engineered the Duramax 6.6-liter V8 diesel delivering more power and torque along with an 11 percent increase in fuel economy on the highway.

The Duramax is linked to an Allison 1000 six-speed automatic transmission that has been strengthened to handle the higher torque capability of the improved diesel engine.

The company said that with the Duramax/Allison combination, preliminary testing showed 0-60 mph times of less than 9 seconds and quarter-mile times of less than 16 seconds in 2500HD models. That's about 0.3-second and 0.5-second quicker, respectively, than previous models.

For those that prefer gasoline fuel, the Vortec 6.0-liter V8 with variable valve timing returns to the new heavy-duty trucks, along with a strengthened version of the Hydra-Matic 6L90 six-speed automatic transmission.

Detailed specifications on both engines are to be released at a later date.

So what does all this mean in terms of towing and payload capability? According to GM, the maximum conventional (ball hitch) towing rating has been increased to 16,000 pounds (7,257 kg), while the 3500HD crew cab/long box can tow up to 20,000 pounds (9,091 kg) with a fifth-wheel hitch. The maximum payload capability for the 3500HD is 6,335 pounds (2,873 kg).

As for the styling updates, most will find it hard to spot the differences as they are limited on the outside to a power dome-style hood with a new, louvered design, restyled grille and full-width chrome steel front bumper plus a new lineup of 17-, 18- and 20-inch wheel/tire combinations.

The new Silverado will go on sale in the States this summer.