The Insurance Institute for Highway Safety (IIHS) has performed its updated moderate overlap front crash test on eight luxury vehicles to test how back row passengers would fare in a collision.

Just three —the Lincoln Aviator, Mercedes-Benz GLE Class, and Volvo XC60 — received good ratings. The Acura MDX and BMW X3 were rated acceptable, while the Audi Q5 and Lexus RX received marginal ratings, IIHS said. 

The Cadillac XT6 was the only model to receive a poor rating.

“It’s encouraging that more than half of the 2024 midsize luxury SUVs we tested performed well in our updated moderate overlap front crash test,” said David Harkey, IIHS president. “The three good ratings in this group show that our new, tougher standards are achievable when manufacturers commit to excellence.”

IIHS launched its updated moderate overlap front test last year after research indicated that in newer models, the risk of a deadly injury is higher for those in the second row than it is in the front. The test emphasizes backseat safety.

Until relatively recently, backseat passengers were less likely to die in a crash because of vehicle design. However, many automakers are now adding advanced seat belts and air bags in the front row but not usually in the back, making the backseat a more dangerous place to be for those traveling in 2007 or newer models, IIHS said.

A recent IIHS study of real-world crashes showed that in many cases, backseat passengers were injured more severely than front-seat occupants.

In the updated test, a second dummy the size of a 12-year-old child is positioned in the second row behind the driver dummy, which is the size of an average man.

“For a vehicle to earn a good rating, there can’t be an excessive risk of injury to the head, neck, chest or thigh, as recorded by the second-row dummy,” IIHS said in a press release. “The dummy should remain correctly positioned during the crash without ‘submarining,’ or sliding forward beneath the lap belt, which increases the risk of abdominal injuries.”

It added that the head should remain a safe distance from the vehicle interior and that the shoulder belt should remain properly in place.

The test is also meant to ensure that the cabin maintains enough survival space for the driver, who should not show excessive risk of injuries.

IIHS said that while all eight of the vehicles provided “excellent” front seat protection, the Aviator, GLE Class, and XC60 also protected the back-row occupants. It did note that the Aviator’s rear seat dummy came closer to the front seatback than is ideal and that the GLE-Class dummy indicated an elevated risk of head or neck injuries.

Danny Gredinberg, Database Enhancement Getaway (DEG) administrator, said Mercedes has rear seat belt feeders that automatically extend the belt to “positively influence seat belt behavior.”

“I believe this would be a good function test that needs to be verified after accident repairs are complete,” Gredinberg told RDN.

Mercedes advises in its owner manual that seat belts should be immediately checked by a qualified specialist.

He encouraged repairers to take advantage of free owner’s manual links available through DEG to learn more about seatbelt-related OEM directives.

For the MDX and X3, IIHS said that while the injury measurements were within an acceptable range, the rear dummy’s motion during the test was concerning.

“In the Acura MDX, the rear dummy submarined beneath the lap belt, increasing the chances of abdominal injuries. In both the MDX and the BMW X3, the rear passenger dummy’s head also came close to the front seatback, which raises the risk of head injuries,” IIHS said. “Submarining was also a problem for the two marginal-rated SUVs.”

Measurements from the rear dummies indicated a slightly elevated risk of neck or head injuries in the Q5 and chest injuries in the RX, IIHS said. 

In the poorly-rated XT6, the rear dummy submarined beneath the lap belt, and measurements showed there was a moderate risk of head or neck injuries and a high risk of chest injuries.

“Though several vehicles in this class performed extremely well, the fact that we saw submarining in half the models we tested shows that many manufacturers still have work to do to improve restraint systems in the second row,” Harkey said.

IIHS has previously performed the updated moderate overlap front crash test on pickups, midsize cars, and minivans.

Images

Featured image courtesy of Insurance Institute for Highway Safety