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Why Ford took the plunge on the aluminum F-150

Alan Mulally: "Pound for pound, aluminum is stronger and tougher than steel. We have the best alloys we've ever had. This is the material of choice going forward."

Why did Ford Motor Co. take the plunge and decide to build an aluminum-bodied 2015 F-150 pickup?

After all, moving from welded-steel construction of the cab and cargo bed to lightweight aluminum meant higher material costs, a huge investment in tooling and engineering, the risk of a complicated and troubled production launch and potential consumer resistance -- on the highest-volume vehicle in the United States.

A big gamble? Ford didn't see it that way, and here's why.

• Weight savings of up to 15 percent compared with 2014 models means improved fuel economy and a better ability to meet more stringent CAFE rules. Ford is said to be aiming for 30 mpg on the highway from the 2015 F-150 -- within shouting distance of the government's 2025 standard of 30.2 city/highway for full-sized pickups.

• Ford has lots of institutional knowledge about aluminum forming and manufacturing. The F-150 uses the same bonding process developed by Ford for the Jaguar XJ luxury sedan and the Range Rover SUV more than a decade ago.

• The manufacturing footprint of the assembly line will remain about the same. Rivet guns that replace spot welders add complexity, but aluminum could allow other processes, such as painting, to be simplified.

• And there's another critical factor. CEO Alan Mulally spent decades working with high-strength aluminum alloys while building airplanes at Boeing. The boss was confident.