The U.S. will save a lot more gasoline by improving the fuel efficiency of gas-guzzling high-volume pickup trucks than it will swapping out Toyota Corollas for Prius hybrids.

That's mathematical fact.

Now, finally, the makers of the three most popular pickup truck lines sold in the U.S. are boosting the fuel economy offered in new trucks for 2014.

The trend began in 2011, when Ford launched its F-150 with an EcoBoost engine option that delivered V-8 power with the EPA ratings of a V-6 engine.

And it's picking up steam for next year, with GM touting the projected mileage ratings of its all-new 2014 Chevy Silverado and GMC Sierra pickups.

Not all the figures are available yet, but here's our roundup of pickup truck fuel-economy figures--both official and projected--so far.

CHEVROLET SILVERADO: 19 mpg now, 20 mpg to come?

So far, only two models of the new 2014 Chevrolet Silverado pickup have been rated on the EPA site.

The rear-wheel-drive C15 model gets a combined 19 mpg (16 mpg city, 23 mpg highway), and the four-wheel-drive K15 model comes in at 18 mpg combined (16 mpg city, 22 mpg combined).

Those ratings are achieved by the redesigned 5.3-liter V-8 engine paired with a six-speed automatic. The trucks will also be offered with a V-6 and a second V-8 as well.

The previous best Silverado was the Silverado 1500 rear-wheel drive model, rated at 17 mpg combined.

The near-identical 2014 GMC Sierra C15 2WD and K15 4WD models earn exactly the same ratings as their 2014 Chevy Silverado counterparts.

But General Motors said last Wednesday that the 2014 Silverado fitted with its V-6 option will match the best rating for any pickup on the market, which is currently 20 mpg.

The 4.3-liter V-6 paired to a six-speed transmission will achieve a combined 20 mpg rating (18 mpg city, 24 mpg highway) for the rear-wheel-drive model.

Adding four-wheel drive cuts that to 19 mpg combined (17 mpg city, 22 mpg highway).

The base V-6 model will arrive in showrooms by the end of September; the first trucks with the $895 upgrade to the 5.3-liter V-8 are now starting to appear at dealers.

2013 Ford F-150 Lariat

2013 Ford F-150 Lariat

FORD F-150: 18 mpg

According to spokesman Mike Levine, the 2014 Ford F-150 lineup won't have any changes that affect its fuel-efficiency ratings.

So the best gas-mileage rating for a 2014 Ford F-150 is likely to remain the 18 mpg combined (16 mpg city, 22 mpg highway) for the rear-wheel-drive model with the 3.5-liter EcoBoost turbocharged engine, paired with a six-speed automatic transmission.

Adding four-wheel drive to the EcoBoost engine drops the combined rating to 17 mpg (15 mpg city, 21 mpg highway).

All of Ford's V-8 models do less than the 18 mpg of the rear-drive EcoBoost model.

Ford has been surprised at the sales of the V-6 EcoBoost engine in the F-150. Just four months after launch, it and another V-6 represented one-third of all F-150s sold.

The company says the EcoBoost percentage has grown since then.

RAM 1500: 20 mpg

The current 2013 Ram 1500 was updated to boost gas mileage, with active grille shutters, a new 3.6-liter V-6 engine option, and an eight-speed automatic transmission.

That made it the gas-mileage champ among full-size pickups for 2013, with a 20-mpg combined rating (17 mpg city, 25 mpg highway) in rear-wheel-drive form.

2013 Ram 1500 Off Road: 30 Days Of Ram

2013 Ram 1500 Off Road: 30 Days Of Ram

Opting for four-wheel drive with that engine/trans combination takes the combined rating to 19 mpg.

If you want a V-8 in your Ram, the 5.7-liter V-8 with six-speed automatic rates 16 mpg combined with rear-wheel drive.

Ram offers no fewer than four engine/transmission combinations in four-wheel-drive Ram 1500 picukps, but that rear-wheel-drive V-6 model remains the champ.

Shortly, Chrysler will launch a Ram 1500 EcoDiesel with a diesel engine for 2014, the only half-ton pickup for that model year to offer one.

It will use the same 3.0-liter V-6 turbodiesel V-6 as in the 2014 Jeep Grand Cherokee EcoDiesel, where it's rated at 240 horsepower and 420 pounds-feet of torque.

Sales are expected to start before the end of September.

We'll update this article in future as more ratings are released.


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