Ford's 2015 F-150 crew cab model has been named a Top Safety Pick by the Insurance Institute for Highway Safety, while the extended cab model was rated as good by the group.

This spring, Ford's aluminum-body F-150's three cab configurations, including the regular cab model, achieved 5-Star ratings from the National Highway Traffic Safety Administration.

The 2015 F-150 crew cab, called the SuperCrew, earned good ratings in all five assessments performed by the insurance industry group, including small overlap front, moderate overlap front, side, roof strength, and head restraint evaluations. The vehicle is not eligible for the institute's Top Safety Pick+ award because it lacks an autonomous braking system.

The F-150 extended cab (SuperCab) earned good ratings in four of the five evaulations. The institute gave it a marginal rating for occupant protection in a small overlap front crash test. The institute usually only evaluates the top-selling model, which is the F-150 crew cab, but added the extended cab model due to its high volume of sales.

In the small overlap test, an F-150 travels 40 mph toward a 5-foot-tall rigid barrier. The test replicates what happens when the front corner of a vehicle collides with another vehicle or an object such as a tree or a utility pole. In this test on the F-150 exteded cab, intruding structure seriously compromised the driver's survival space, resulting in a poor structural rating, according to the institute.

The IIHS also analyzed repair costs because damage to aluminum body parts can be more complicated and pricier to repair than steel, the Highway Loss Data Institute has found.

The institute ran crash tests at 10 mph with the 2015 F-150 crew cab and its 2014 steel-bodied predecessor. Engineers crashed the front left corner of the aluminum pickup into the right rear corner of the steel pickup at a 15 percent overlap, and then flipped the test and ran the steel pickup into the back of the aluminum one.

In both test scenarios, the aluminum F-150 had more extensive damage than the steel model. Total repair costs for the front and rear damage combined were 26 percent higher for the aluminum F-150. Extra time to repair the aluminum body accounted for the higher price to fix frontal damage, while higher parts costs pushed up the repair bill for the rear damage, according to the institute.

Ford disagrees with the institute's assessment on repair costs, the company said in a release.

"Ford’s view is based on real-world accident repair data," according to Ford. "In fact, real-world repair costs on the new 2015 Ford F-150 average $869 less than last year’s F-150 model, according to Assured Performance, an independent body shop certification company that works with leading automakers."