More than half of the 87 light trucks, pickups and sport utility vehicles tested for rear crash protection by the Insurance Institute for Highway Safety provided only marginal or poor protection from neck injuries.
Head restraints in dozens of sport utility vehicles, pickup trucks and minivans fell short in simulated crashes conducted by the insurance group.
The IIHS reported that the simulated rear crashes at 20 mph showed that many large vehicles did not adequately protect against neck injuries, which lead to 2 million insurance claims a year.
The test results found that several SUVs had improved protections against whiplash injuries, but the IIHS gave poor marks to vehicles made by several automakers, including BMW AG, DaimlerChrysler AG, Ford Motor Co., General Motors Corp., Nissan Motor Co. and Toyota Motor Corp.
But David Zuby, vice president of vehicle research for the IIHS, said the test results showed there was plenty of room for improvement.
"In stop-and-go commuter traffic, you're more likely to get in a rear-end collision than any other crash type," said Zuby. "It's not a major feat of engineering to design seats and head restraints that afford good protection in these common crashes."
Neck injuries are the most common reported in auto crashes, accounting for 2 million insurance claims annually, according to IIHS.
Safety experts say the head and torso must move together to minimize the risk of whiplash. Head restraints must be high enough and close to the back of the head, and seats should meet certain stiffness criteria.
The institute's tests included measuring seat geometry and simulating crashes at 20 miles per hour using a dummy designed to measure neck forces. Performances were rated either poor, marginal, acceptable or good.
In the 2007 evaluation, 17 of 59 SUV models were rated good and five were acceptable. The remaining 37 were marginal or poor. In 2006, only six of 44 SUVs earned good ratings.
In vans, three were rated good and two acceptable. In pickups, one model posted a 'good' score, while five were acceptable. The remaining 11 were marginal or poor.
The redesigned 2007 Tundra from Toyota was the only pickup that received a good rating.
The best performers among 2007 SUVs included the Acura MDX and RDX; Lincoln MKX; Ford Edge; Honda CR-V, Element and Pilot; Hyundai Santa Fe; Jeep Grand Cherokee, and Volvo XC90.
SUVs from the 2007 model year rated poor included the GMC Envoy, BMW X3 and X5 and the Toyota 4Runner and Highlander.
