Ready to get dirty? The first production examples of Ford's all-new 2015 F-150 rolled off a Dearborn assembly line this past week, Ford said on Friday. Source: Ford Motor Co.

Ford Motor Co. (NYSE:F) said on Friday that one version of its all-new 2015 F-150 pickup will have the "highest EPA-estimated fuel economy rating among gas-powered pickups."

Ford has been promising great fuel economy from this new truck for months. But on Friday, it got specific: The automaker said a 2015 F-150 in 4x2 drive configuration equipped with Ford's 2.7-liter turbocharged "EcoBoost" V6 will carry EPA-estimated ratings of 19 miles per gallon city, 26 mpg highway, and 22 mpg combined.

That's an improvement of 5% to 29% over the outgoing F-150, Ford said.

Twenty-two mpg combined for a full-size pickup is impressive, but that seems like a lot of fine print. Is this really a big deal?

Yes, it's a big deal. Here's why.
Here's the takeaway, as Ford product chief Raj Nair put it in a presentation to journalists on Friday: For someone who drives 15,000 miles a year, that 2.7-liter EcoBoost F-150 will save you over $400 annually in fuel costs versus the ranking overall fuel-economy champ, Fiat Chrysler's (NYSE:FCAU) Ram EcoDiesel, while providing strong performance, payload, and towing capacity.

That's the payoff from Ford's decision to build its new trucks with aluminum body panels, making them hundreds of pounds lighter, and from Ford's major investment in advanced turbocharging technology.

Why is that a big deal? Because a lot of full-size pickups get sold to commercial fleet buyers. For those buyers -- and for some individual consumers, too -- the total annual cost to own and operate a truck is a huge buying consideration.

Ford's new 2.7-liter twin-turbo "EcoBoost" V6. Expect to hear a lot about this new engine in Ford's truck ads next year. Source: Ford Motor Co.

Nair noted that the average full-size pickup being traded in is about seven or eight years old, and so made several comparisons between the new truck and an F-150 from 2008. 

Comparing the 2.7-liter EcoBoost-powered 2015 F-150 to a V8-powered 2008 F-150, the new truck has more horsepower, more torque, higher towing capacity, and a higher payload, with significantly better fuel-economy ratings than the old truck's 14 mpg city and 19 mpg highway.

That "little" V6 stacks up pretty well against the other guys' V8s, too
The performance of that 2.7-liter EcoBoost truck will also compare well with V8-powered rivals, while trouncing them in fuel economy. The V8-powered versions of the Ram and General Motors' Chevy Silverado edge out the V6 Ford in towing capacity, but not in payload -- and the Ford has Toyota's V8-powered Tundra beat on all fronts.

Of course, if you need more performance, you can choose a more powerful 3.6-liter EcoBoost V6 or a 5-liter V8 for your new F-150. Both also post solid fuel-economy numbers, though the V8 F-150's 15 mpg city and 22 highway is beaten by the 5.3-liter V8-powered Silverado's 16 mpg city and 23 highway.

Still, that new 2.7-liter EcoBoost V6 gives Ford a lot to brag about in its ads. But more important, it gives Ford a compelling sales story to present to its commercial customers: Our new truck will give you the performance you need while saving you money.

Ford is betting that the new F-150's fuel economy will be a big selling point with commercial buyers. Source: Ford Motor Co.

But while Ford can argue (persuasively) that it's cheaper to own, that 2.7 EcoBoost doesn't beat the EPA ratings of the reigning overall fuel-economy champ among full-size pickups: the Ram 1500 EcoDiesel. Why didn't Ford go for the top crown with a diesel of its own?

Why Ford isn't taking on the diesel Ram -- yet
Ford has hinted for a while that it wouldn't try to beat the diesel-powered Ram's top fuel-economy numbers. Nair pointed out that gasoline is currently significantly cheaper per gallon than diesel -- $2.89 versus $3.66, according to U.S. government figures from earlier this week.

That's a big gap, but diesel fuel has been somewhat more expensive than unleaded regular gasoline for a while now. Nair argued that the Ram EcoDiesel's small fuel-economy advantage is more than offset by that price disparity, not to mention the higher cost ($4,000) of the diesel option itself.

Ford, of course, offers diesel engines in its Super Duty pickups, but not in the F-150. That could change, Nair said, if the price of diesel fuel were to fall to the point at which it becomes a cost-efficient choice for Ford's customers.

But for now, Ford is pinning its fuel-economy bragging rights on its gasoline-powered EcoBoost engines. Given the success of its current EcoBoost offering -- about 40% of 2014 F-150s are EcoBoost-powered -- the new 2.7-liter version should find plenty of interested customers. How will sales fare? Stay tuned.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.