2014 Chevrolet Silverado and GMC Sierra revealed

General Motors has unveiled its all-new 2014 Chevrolet Silverado and GMC Sierra full-size pickup trucks, the most important models introduced since the company was bailed out by the federal government four years ago.

Last redesigned in 2007, the near-twin Silverado and Sierra make up the company’s best-selling vehicle line and one of its most profitable. GM is believed to make about $10,000 on each one sold.

The automaker touts the new trucks as both more capable and efficient than the ones they replace. At the unveiling, GM North America President Mark Reuss called them the "most refined pickup trucks ever."

Following a trend seen in recent Ram and Ford pickup designs, the Silverado takes on a tougher appearance than the model it replaces. Although evolutionary in design, its signature stacked headlights and twin-port grille are larger and more prominent than before, while the slab sides of the outgoing Silverado are replaced with sculpted shapes and bulging, squared-off wheel arches. The Sierra sticks with a pair of solo headlights and a single-opening grille with a thick chrome frame.

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Meanwhile, the aerodynamics of the pickups have been improved with a more swept back windshield, a hood with twin “power domes” that direct air over the windshield wipers, triple-sealed doors set into the body, integrated rooftop and tailgate spoilers and shields and deflectors to smooth the airflow under the vehicle and around the rear tires for better fuel efficiency and reduced wind noise.

Three new engines will be offered in the trucks, a 4.3-liter V6, 5.3-liter V8 and 6.2-liter V8 that is similar to the one that will be used in the 2014 Chevrolet Corvette. Specifications on the powerplants have not been revealed, but all of them feature direct injection, variable valve timing and cylinder deactivation technology that allows them to operate on just four-cylinders under light loads to save fuel.

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GM promises that the 6.2-liter will be the most capable engine in the class. The version in the corvette is expected to deliver at least 450 hp and 450 lb-ft of torque.

The cabins of the new trucks exhibit a more dramatic change than their exteriors, but still stick to the utilitarian theme. GM says potential customers it talked to were asking for a more functional interior than some of the car-like designs seen in the market today.

An upright dashboard with big knobs, buttons and rocker switches close that can be operated with work gloves on are key elements of the design. Heated cloth seats will be available for the first time, and the upholstery is said to be more durable and stain resistant than before. Chevrolet's MyLink and GMC's Intellilink infotainment systems, which can connect to up to 10 wireless devices via Bluetooth, will be on the options list, and GM says the compartment built into the center console is large enough to accommodate a laptop computer and hanging file folders.

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One unique exterior feature is the new CornerStep bumper, which has steps integrated in either side of the tailgate make it easier to climb into the truck bed, while the tailgate itself has an integrated torsion bar and rotary damper to reduce the effort needed to open and close it.

The pickups will make their public debut at the 2013 North American International Auto Show in Detroit on January 14th and are expected to go on sale in the spring.

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