General Motors has released gas-mileage ratings for the 2015 Chevrolet Colorado and 2015 GMC Canyon mid-size pickup trucks equipped with the base four-cylinder gasoline engine.

Trucks equipped with the 2.5-liter engine and six-speed automatic transmission will return an EPA-estimated 22 mpg combined (20 mpg city, 27 mpg highway).

With four-wheel drive, the Colorado and Canyon lose one mpg in the combined and city categories, and two mpg in the highway category.

MORE: 2015 Chevy Colorado, GMC Canyon Prices: $21K And Up, $5K Lower Than Full-Size Pickups

GM will also offer a six-speed manual transmission in basic Work Truck models. Only available with rear-wheel drive, it achieves the same combined and city ratings as the six-speed automatic, but loses one mpg in the highway category.

Producing 200 horsepower and 191 pound-feet of torque, the 2.5-liter four-cylinder's fuel-economy ratings aren't dramatically higher than the 3.6-liter V-6 that will be optional in both trucks.

2015 Chevrolet Colorado Z71

2015 Chevrolet Colorado Z71

Using the same six-speed automatic available with the four-cylinder, the V-6 will achieve 21 mpg combined (18 mpg city, 26 mpg highway) with rear-wheel drive, and 20 mpg combined (17 mpg city, 24 mpg highway) with four-wheel drive. It also produces 305 hp and 269 lb-ft of torque.

The V-6 mid-size trucks, in turn, are not much more fuel efficient than the full-size Chevrolet Silverado pickup equipped with a 4.3-liter V-6 and six-speed automatic.

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The Silverado is rated at 20 mpg combined (18 mpg city, 24 mpg highway) with rear-wheel drive, and 19 mpg combined (17 mpg city, 22 mpg highway) with four-wheel drive.

That's because, while the Colorado and Canyon are smaller than full-size trucks, they're still rather large vehicles.

For the 2016 model year, a 2.8-liter Duramax diesel four-cylinder engine option will also be available, giving buyers potentially greater fuel efficiency.

It won't go on sale until next year, though, while the gasoline Colorado and Canyon will arrive in dealerships later this fall.


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