Ford's aluminum-sided F-150 pickup saw mixed results in new crash tests.
The four-door Super Crew version of the 2015 F-150 got top ratings in all five crash tests performed by the Insurance Institute for Highway Safety. For now, it is the only full-size truck on the market with the institute's "Top Safety Pick" rating.
But the smaller Super Cab version did poorly on one frontal crash test.
The insurance institute says aluminum is safe and performed well. The different results were due to a design difference in the steel frame beneath the aluminum sides.
Ford noted that the trucks earned the government's top safety ratings. But it says it will improve the design of the Super Cab and Regular Cab trucks in 2016 so they perform better in front crashes.