GM considering diesel option for light-duty full-size pickups

The Chevy Silverado and GMC Sierra 1500 could be in line for an efficient turbodiesel motor.

General Motors may offer a diesel option on its Chevrolet Silverado and GMC Sierra 1500 to help the pickups keep pace with increasingly efficient rivals.

In their most economical form, GM's full-size, light-duty pickups return 24 mpg on the highway. That's considerably less than the 28 mpg expected from the upcoming Ram EcoDiesel and the 30 mpg target Ford has set for its aluminum-bodied 2015 F-150.

However, a diesel powerplant could bring the Silverado and Sierra right back into the thick of the fuel economy battle.

"We are looking closely at diesel entrees in that segment," Steve Kiefer, GM's vice president of global powertrains, told Automotive News on the sidelines of the Detroit show.

"In fact, I heard the terms 'dust off' that 4.5-liter at one point,” Kiefer said. "That is certainly one of the options. Clearly, we have a portfolio of diesel engines.”

The 4.5-liter referenced by Kiefer, a light-duty truck V8 that GM was forced to shelve in 2009 due to financial difficulties, was rumored to produce around 300 horsepower and 520 lb-ft of torque. The mill could provide a balance of power and efficiency in the mold of the 2015 Nissan Titan's Cummins V8, although it likely wouldn't be as efficient as the Ram EcoDiesel's smaller V6.

With U.S. consumers showing increased interest in oil-burning engines, GM is working to expand diesel availability throughout in its lineup. Last year, it launched a 46-mpg turbodiesel version of the Chevrolet Cruze compact and announced plans to make diesels available in its redesigned midsize pickups. The automaker is also weighing whether to fit the aforementioned 4.5-liter to its 2015 full-size SUV range.

Photo by Mark Elias.