Crew-cab versions of Ford's new F-150 aced a recent crash test -- but extended-cab versions like this one didn't. Ford says that the 2016 extended-cab "SuperCab" model will include a steel brace that should help. Source: Ford Motor Company

Ford's (F 1.43%) all-new F-150 pickup made headlines this past week. But they weren't the kind of headlines that Ford likes.

The gist of the story is that an extended-cab version of the new F-150 suffered damage during a crash test that presented a risk of serious injury to the driver. That led to some harsh headlines suggesting that the new truck's aluminum construction might be to blame.

The findings came from a series of crash tests administered to new F-150s by the Insurance Institute for Highway Safety, or IIHS. But the IIHS issued a press release giving the new F-150 high overall marks for safety -- and Ford says that crash tests prove that the F-150 is the safest full-size pickup.

What's the deal?

F-150 SuperCrew aced the tests, but F-150 SuperCab missed 1 out of 5
The IIHS tested two versions of the F-150 in five different crash tests. The crew-cab version of the F-150 (which Ford calls "SuperCrew") aced all five tests and earned the Institute's "Top Safety Pick" rating.

The extended-cab version, which Ford calls "SuperCab," did well in four of the five tests. But it got a "marginal" rating in the small overlap front crash test, which seeks to replicate what happens when a vehicle hits a tree or utility pole or similar object at 40 miles per hour. 

The impact in this test is on the driver's side, and it covers 25% of the vehicle's total width. 

So why did one F-150 pass and one fail? The answer seems to come down to a steel structure that Ford added to the larger F-150 to help it resist crash damage -- but that wasn't included on the smaller SuperCab version.

This 2015 F-150 features the "SuperCrew" crew-cab, distinguished by its additional door for rear-seat passengers. The SuperCrew body style, which accounts for the vast majority of F-150 sales, aced the IIHS crash test and earned a "Top Safety Pick" designation. Source: Ford Motor Company

Testing both versions of the F-150 was a departure for the IIHS. It says that for vehicles with multiple body styles, like the F-150, it typically evaluates just one, the version with the biggest sales. For the F-150, that's the crew cab. But because of the new F-150's aluminum construction -- and because the extended-cab F-150 is also a big seller -- IIHS in this case chose to evaluate the smaller truck as well.

The IIHS's chief research officer, David Zuby, seems to think the results raise an uncomfortable question for Ford.

"Ford added structural elements to the crew cab's front frame to earn a good small overlap rating and a TOP SAFETY PICK award but didn't do the same for the extended cab," Zuby said in a statement. "That shortchanges buyers who might pick the extended cab thinking it offers the same protection in this type of crash as the crew cab. It doesn't."

Did Ford try to game the crash tests?
Did Ford try to game the crash tests by adding extra reinforcement to the version of the F-150 most likely to be tested -- while leaving it out of the others?

Not quite, according to Ford product chief Raj Nair. Speaking to Bloomberg, Nair pointed out that the small overlap crash test is a fairly new test. It was added to the IIHS's testing regimen in 2012, while the new F-150 was still under development. Ford chose to address it in the SuperCrew version of the F-150 first simply because SuperCrew versions represent 83% of Ford's F-150 sales volume, Nair said. 

After the results were released, Ford said that it plans to add the extra steel to all versions of the F-150 starting with the 2016 model year, which goes into production in a few months.

So does this mean the F-150 is unsafe?
Not at all. 

Ford noted that in crash tests administered by the U.S. government's National Highway Traffic Safety Administration, all versions and configurations of the new F-150 received five stars, the highest rating. Ford says that it's the only full-size light-duty pickup to get five stars in all versions.

For its part, the IIHS pointed out that the F-150 is the first full-size pickup to go through the new small overlap crash test  -- and that means the F-150 SuperCrew is the first full-size pickup to get an IIHS "Top Safety Pick" rating under the new testing regimen.

The upshot: This isn't likely to dent Ford's sales much
Truck buyers are a conservative lot. I suspect that some will never believe that an aluminum-bodied truck can be as safe or durable as a steel-bodied one. These test results -- and some of the headlines that resulted -- will surely play into those concerns.

But the reality is that Ford's F-150 SuperCrew did well in a tough new test that rival pickups have yet to face -- and both of the versions of the F-150 that were tested did well on the other four tests administered by IIHS. While the result was an awkward moment for Ford, it's unlikely to scare many potential F-150 buyers away from dealers.