Even pickup trucks are getting better gas mileage these days.

The 2014 Chevrolet Silverado 1500 (and its 2014 GMC Sierra 1500 twin) with the 6.2-liter V-8 has been rated with significantly better fuel efficiency than last year's model.

The EPA ratings are 15 mpg city and 21 mpg highway for rear-wheel-drive models, and 14 mpg city and 20 mpg highway for four-wheel-drive models.

Combined ratings have not been released, but we expect them to be around 17 mpg for rear-wheel drive and 16 mpg for four-wheel drive.

The outgoing Silverado 1500 with the 6.2-liter V-8 is rated at 14 mpg combined (13 mpg city, 18 mpg highway with rear-wheel drive, and 12 mpg city, 18 mpg highway with four-wheel drive).

Increases of 2 or 3 mpg may not seem like much, but in fact they represent improvements of around 15 percent city and 14 percent highway for rear-drive models and 16 percent city and 11 percent highway for four-wheel drive models.

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The boost in fuel economy is partially due to the many improvements GM has made to the big V-8 for 2014.

The redesigned Silverado's biggest gasoline engine now boasts fuel-saving technologies like direct injection and cylinder deactivation, as well as a lighter aluminum block and heads.

Chevrolet also offers the Silverado with a 4.3-liter V-6 and a smaller, 5.3-liter V-8.

EPA ratings for the V-6 are 20 mpg combined (18 mpg city, 24 mpg highway) for rear-wheel drive and 19 mpg combined (17 mpg city, 22 mpg highway) for four-wheel drive.

The 5.3-liter V-8 is rated at 19 mpg combined (16 mpg city, 23 mpg highway) for rear-wheel drive and 18 mpg combined (16 mpg city, 22 mpg highway) for four-wheel drive.

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