Light weight will soon be big business at Ford.

The company's F-150 truck, going aluminum for the first time with the 2015 model, sheds 700 lbs over its predecessor, thanks to its new construction. Ford sells over half a million F-Series every year--big business indeed.

This technology and other lightweight materials could also be used to cut the weight of a car like the Fusion sedan by a quarter, according to Ford.

As Wards Auto reports, the firm has developed a 'Lightweight Concept Car' based on the Fusion.

Externally similar to Ford's volume sedan, the Lightweight concept uses a mix of high-strength steel, aluminum, magnesium and carbon fiber. There's also polycarbonate glazing, and a set of narrow wheels and tires.

The body is aluminum. Brake rotors are aluminum coated with steel. The car's coil springs are made of composites and hollow steel. Stabilizer bars are also hollow, while some components, like the oil pan, are made from carbon fiber.

The weight gains also have exponential benefits. Less weight means less effort is needed to move the vehicle, enabling Ford to fit its 1.0-liter Ecoboost three-cylinder in the engine bay in place of larger 1.6 and 2.0-liter units.

And by fitting the tiny Ecoboost unit, weight is reduced further. It's a virtuous circle.

The end result is a car that weighs around 2,400 pounds. That's around 800 pounds less than the lightest Fusion you can currently buy--and isn't far off the curb weight of a Fiesta subcompact.

Ford admits that while the Fusion uses techniques and materials that are already available and in use in the car industry--technical leader for materials, Matt Zaluzec, says it's "not a leap of faith"--such a car isn't exactly production ready.

Ford Fusion Lightweight Concept

Ford Fusion Lightweight Concept

All those high-tech materials are expensive, for a start. And along with cost, the car's relative performance deficit to a regular Fusion would also pose a problem.

The Detroit News notes that the Big Three made a similar observation in the late 1990s and early 2000s with three, 70 mpg-plus concept vehicles.

The GM Precept, Ford Prodigy and Chrysler ESX-3 were all diesel hybrids, but all would have cost too much and offered performance below that of customer expectations. None made it into production.

That's not to say that elements of the Lightweight Concept won't make production, though. Ford is using it as a technical exercise to determine where the biggest gains can be made.

Indeed, many of the concept's attributes may reach production at some point, though automakers are counting the pennies as high-tech materials can raise costs in unexpected ways. A lightweight carbon fiber seat frame could cost $53-$73--a conventional steel one is currently $12.

And high-tech materials alone won't allow automakers to hit 2025 Corporate Average Fuel Economy targets of 54.5 mpg.

Bob Lutz, speaking to The Detroit News earlier this year, suggests engines, transmissions and plug-in hybrid technology will all play a part. Lutz himself is backing the latter, in the form of Via Motors' range-extended trucks, based on GM vehicles.

In other words, that 54.5 mpg target isn't out of reach, but a whole range of technologies will be necessary for regular, everyday vehicles to reach it.

That may well push up the cost of future vehicles--but in theory, gains made in efficiency and even performance will more than offset the extra purchase price. What looked out of reach just over a decade ago now looks entirely plausible.


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