Ford's aluminum F-Series gets mixed reviews

The results of new crash tests involving Ford (F)'s F-Series pickup trucks raised some concerns about the cost of repairs. But more importantly, they dismissed warnings from skeptics who have suggested the first pickup featuring aluminum panels is not strong enough to protect passengers.

The Insurance Institute for Highway Safety conducted a series of crash tests on Ford's F-150 SuperCrew pickup and the extended-cab version of the new F-150. The SuperCrew earned top "good" ratings from the IIHS in all five crash tests, while the extended-cab model scored that same rating in four of the five tests.

"Consumers who wondered whether the aluminum-body F-150 would be as crashworthy as its steel-body predecessor can consider the question answered," said David Zuby, chief research officer at IIHS.

The one area in which there was a difference in performance between the two versions of the truck involved the small overlap crash test, where the front driver side of the pickup slammed into a barrier at 40 mph.

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While the SuperCrew passed the test with a "good" rating, the extended-cab F-150 was given a "marginal" performance grade. IIHS said measurements on the crash test dummy indicated there would be a moderate risk of injury to drivers involved in a similar accident in the real world.

"The extended cab is still a safe vehicle, but for those people shopping for the safest vehicle, they should put their emphasis on the crew cab," Zuby said. "It clearly provides better protection in [a] wider variety of frontal crashes than the extended-cab version."

Ford says the extended cab F150 was in the midst of development when requirements to improve the safety of vehicles involved in small overlap crashes were passed, so the 2015 model could not include the necessary design changes. But the company says that is changing.

"We're moving to add... counter measures for the super cab and regular cab for the 2016 model year," said Ford spokesman Mike Levine.

The F-Series is the best-selling vehicle in the U.S. Ford has already declared the new, lighter version a hit based on strong sales since it rolled out late last year.

Ford's arch rival, General Motors (GM), has been running a series of commercials where people have to choose between a steel cage or an aluminum one to get away from a grizzly bear.