The Ford F-150 full-size pickup is the best-selling single nameplate in the U.S. market, so any changes to Ford's premier truck mean a lot.

Buyers, dealers, and the whole industry are paying close attention to information about the next generation 2015 Ford F-150, the first all-new design of Ford's truck since the 2009 model.

Ford Atlas Concept at the 2013 Detroit Auto Show

Ford Atlas Concept at the 2013 Detroit Auto Show

And fuel efficiency will be one of the most closely-watched specifications.

MORE: 2014 Pickup Truck Gas Mileage: Ford vs Chevy vs Ram, Who's Best?

This year, the new best combined gas-mileage for large pickup trucks is 20 mpg--achieved by versions of the 2014 Chevrolet Silverado C15 and the 2014 Ram 1500.

Lighter weight

While Ford lags behind, at 18 mpg combined, it's clear the company will want to meet--and more likely beat--the 20-mpg figure, targeting a combined gas-mileage rating for the best model of its new 2015 F-150 to 21 mpg or higher, possibly as high as 23 mpg.

The company is known to be using much more aluminum in the next F-150, though recent rumors say quality problems in getting acceptable panel quality could delay the new F-150's production launch from six to 10 weeks.

Thus far, there's been no indication that Ford plans to debut the new F-150 pickup truck at the next Detroit Auto Show, which opens to the press three weeks from today.

Ford Atlas Concept

Ford Atlas Concept

That could depend on whether Ford can get the alleged problems resolved and keep the truck on track for a summer launch.

Reducing drag

Other likely fuel-saving technologies include active grille shutters (already used on the current Ram pickup), retractable running boards, and a front air dam that can be extended at speed to reduce aerodynamic drag.

Last January, Ford showed these features plus an additional innovation--active wheel shutters--on the Ford Atlas Concept pickup truck, its main concept vehicle at the 2013 Detroit Auto Show.

MORE: Ford F-150 Atlas Concept: A Transit Pickup Truck Stays In Step In Detroit

Because pickups need large wheels, the aerodynamic turbulence created by air flowing past and through them is greater than on passenger cars with smaller wheels.

Taken together, Ford says all these techniques could add 2 mpg to a new pickup's gas-mileage rating. Whether that's from 18 mpg to 20 mpg, or more likely higher, remains to be seen.

Ford Atlas Concept at the 2013 Detroit Auto Show

Ford Atlas Concept at the 2013 Detroit Auto Show

Atlas, by the way, is the mythological figure who is strong enough to carry the world on his shoulders. Ford said at the Atlas Concept introduction that many of the people who drive its pickup trucks see themselves that way.

Smaller engines

Another tactic to boost gas mileage is using smaller engines, which are found these days across vehicles in every segment to meet steadily increasing corporate average fuel economy (CAFE) mandates.

The 2015 F-150 will clearly carry on with a powerful and high-torque V-8 at the high end, for towing capacities of 10,000 pounds or more, along with both conventional and turbocharged V-6 engines for higher-volume models.

Ford has been pleasantly surprised by the reception among buyers for its turbocharged 3.5-liter EcoBoost V-6 in its large pickups since their launch in early 2011.

Sales of that model are closing in on half a million, promoted as offering the power of a larger non-turbo V-8 with higher EPA fuel-efficiency ratings.

2014 Ford F-150 Tremor

2014 Ford F-150 Tremor

These engines may well be married to an eight-speed automatic transmission, another advance already pioneered on certain Ram pickups for 2014.

As small as four?

Might we see an EcoBoost four-cylinder F-150? That seems unlikely, but stranger things have happened--and Ford has just launched a new 2.3-liter EcoBoost four-cylinder engine for the 2015 Mustang that it says will produce at least 300 hp.

Unlike Chevrolet, with a mid-size 2015 Colorado pickup on the way--which will offer both a gasoline four-cylinder engine and a 2.8-liter diesel four-cylinder as well as a V-6--Ford has said it sees little market for pickups smaller than the full-size F-150.

So a low-volume F-150 variant with a four-cylinder engine and eight-speed automatic would offer a gas-mileage halo model, even if Ford sold very few.

At the moment, however, that's pure speculation--but then, so was a four-cylinder EcoBoost Mustang just a few years ago.


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