Arlington, Virginia – SUV bumpers that don’t line up with bumpers on cars can lead to huge repair bills in otherwise minor collisions, according to the U.S. Insurance Institute for Highway Safety (IIHS). Bumpers on cars are designed to match up with each other in collisions, but a long-standing gap in federal regulations exempts SUVs from the same rule, the agency said.

“SUVs and cars share the road,” said Joe Nolan, IIHS chief administrative officer. “The problem is they don’t share the same bumper rules, and consumers end up paying the price.”

A U.S. federal standard requires that all cars have bumpers that protect within a zone of 16 to 20 inches (406 to 508 mm) from the ground. This means that they line up reasonably well and are more likely to engage during low-speed collisions to absorb energy and prevent damage. No bumper requirements apply to SUVs, pickups or minivans, so when they do have bumpers they are often flimsier and higher off the ground than bumpers on cars. In fender-benders with SUVs, cars often end up with excessive damage to their hoods, cooling systems, fenders, bumper covers and lights.

The IIHS conducted front-to-rear crash tests at 10 mph (16 km/h) involving seven pairs of 2010-2011 models, each a small car and small SUV from the same automaker. “We picked vehicles from the same manufacturer because we think automakers should at the least pay attention to bumper compatibility across their own fleets,” Nolan said. “The results show that many don’t.”

In the tests, an SUV going 10 mph struck the back of its paired car, which was stopped; the car then was driven into the SUV. Results of these low-speed impacts varied widely, from a total of US$850 damage to one vehicle to $6,015 to another. In some cases, the damage included cooling systems that would have prevented the motorists from driving away from the collision.

In collisions with a Nissan Rogue and Nissan Sentra, the impact crumpled the car’s bumper cover, trunk lid and rear body, while the Rogue ended up with a crushed radiator that prevented it from being driven after the test. The $4,560 for the Sentra was the highest in all cars in the test. In a Ford Escape and Ford Focus, the bumpers overlapped, resulting in $3,386 in repairs to the Focus’ rear body and trunk lid when hit by the Escape. When the Focus struck the back of the Escape, its front bumper underrode the Escape’s rear bumper, causing an additional $5,203 in damage to the Focus.

In testing of a Toyota Corolla and RAV4, the damage was almost $10,000, the highest combined test damage among all of the vehicle pairs. The RAV4 accounted for about $6,000 of the bill.

Bumper combinations that lined up better included the Honda CR-V and Civic, which had combined damage of $2,995, and a Kia Forte and Hyundai Tucson, with a combined $3,601.

In July 2008, the IIHS petitioned the National Highway Traffic Safety Administration (NHTSA) to regulate bumpers on SUVs and pickups the same as cars and require them to match up in a way that shields both vehicles from costly damage. In June 2009, NHSTA agreed to seek comments on the petition but has not moved forward with a rulemaking or a low-speed compliance test for bumpers, the IIHS said.

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