The Ford F-150 pickup might be one of America's best-selling vehicles, but the move to build the 2015 model from aluminum has required significant investment from Ford.

To ensure that investment is worth it, the company is likely to use aluminum in several other vehicles to spread the development cost--and the first of those could be the 2017 Lincoln Navigator.

The Navigator is not your traditional green vehicle. It's big, square, lumbering and requires large engines to power it.

The 2014 car, with its 5.4-liter V-8 engine and six-speed automatic transmission achieves just 16 mpg combined.

Ford knows cars like the Navigator need to be more efficient, however. As Motor Authority reports, Lincoln has already decided to drop the V-8 model from 2015, in favor of the firm's Ecoboost-branded V-6 turbo.

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A hybrid version is also likely, and the old six-speed automatic should soon make way for a ten-speed that Ford is co-developing with General Motors.

Those alone may not be enough to make significant economy inroads, however.

Something must also be done about the Navigator's 5,780 lb curb weight. At its lightest--the heftiest long-wheelbase Navigators weigh over 6,200 lbs.

Automotive News says that a switch to aluminum is likely with the next-gen car, expected to arrive in the second half of 2016 for the 2017 model year.

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In the F-150 pickup, aluminum has managed to slash up to 750 lbs from the weight of some models.

A similar diet for the Navigator would reduce weight to just over the 5,000 lb mark--closer to that of the latest generation Range Rover, a smaller vehicle that also uses aluminum construction to save weight over its predecessor.

As no fuel economy ratings for the 2015 F-Series have yet been released by the EPA, it's hard to predict how much the Navigator might improve with a lighter body and more advanced drivetrain.

What's important though is that one of America's most profligate vehicles could improve significantly in its next generation.


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