Arlington, Virginia – A new low-speed crash test of bumpers on midsize sedans conducted by the U.S. Insurance Institute for Highway Safety (IIHS) found that some have improved, but none performed well enough to earn a “good” rating, and many have tested worse than before.

Bumpers on 2009 models of the Honda Accord, Hyundai Sonata, Mazda6 and Nissan Maxima performed better than their 2007 predecessors, but the 2009 Chevrolet Malibu and 2010 Ford Fusion did worse than earlier models. None of the six popular midsize sedans earned the top “good” rating in a recent series of tests designed to assess and compare how well bumpers resist damage in everyday fender-benders.

The Mazda6 improved to “acceptable” from “marginal,” with an average repair cost of less than US$900 after four tests at three and six mph (4.8 and 9.6 km/h). The Accord and Sonata improved from “poor” to “marginal.” The Fusion slipped from “marginal” to “poor,” while the Maxima and Malibu remained at the “poor” rating.

“Consumers buy midsize cars for practical reasons,” said Joe Nolan, IIHS senior vice-president. “There’s nothing practical about a $1,000-plus repair bill after a minor bump in commuter traffic.”

The IIHS rates bumpers good, acceptable, marginal or poor in four tests: front and rear full-width impacts at six mph, and front and rear corner impacts at three mph. Each vehicle is run into a steel barrier designed to mimic the design of a car bumper, with the barrier’s plastic absorber and flexible cover simulating a typical car’s energy absorbers and plastic bumper covers. The tests are designed to drive bumper improvements that lead to better damage resistance in a range of real-world crashes.

“Although midsize car bumpers still allow way too much damage in minor impacts, it’s encouraging that some manufacturers are designing better ones,” Nolan said. He noted that the front and rear bumpers of the 2009 Mazda6 are wider, taller, and higher off the ground than the 2007 models. It is only the fourth car tested under the new protocol to earn an “acceptable” rating for its bumpers, along with the Ford Focus, Smart Fortwo and Scion xB, a model not sold in Canada.

The IIHS said that Ford and General Motors made design changes that increased repair costs for the 2010 Fusion and 2009 Malibu over repair estimates for the 2007 models. In the full front test, the Fusion had $2,529 in damage, more than any other vehicle. “Ford fit the Fusion’s front and rear with weaker bumper beams, and this had a big effect on the test performance,” Nolan said. “The difference is easy to see in the six mph full rear test, which simulates a common parking mishap like backing into another vehicle. The Fusion’s bumper buckled, which caused it to underride the test barrier, resulting in twice as much damage as the 2007 model in the rear test.”

The Malibu’s rear bumper is now higher than on the earlier model, but is still the lowest among recently-tested bumpers. In the full rear test, the bumper underrode the barrier, resulting in almost $3,500 in damage, the highest among the midsize cars evaluated. In the front test, damage totalled $2,092, partly because the Malibu’s front grille overlays the centre of the bumper, resulting in the grille, emblem and decorative chromed plastic trim getting hit before the bumper did in the test. “Essentially you have to go through them to get to the bumper,” Nolan said. “Replacing just the front grille and emblem cost more than $625.”

The IIHS said that Ford and General Motors, along with other automakers who sell the same vehicles in both the U.S. and Canadian markets, no longer have to meet a tougher Canadian bumper standard. The Canadian government last year weakened its bumper rules to match U.S. regulations, which require only minimal protection.

The designs of ten other midsize cars hadn’t changed since their bumpers were last tested in the 2007 model year. In those tests, “marginal” ratings went to the Mitsubishi Galant and Toyota Camry. “Poor” ratings went to the Chrysler Sebring, Nissan Altima, Pontiac G6, Saturn Aura, Subaru Legacy, Volkswagen Jetta, Volkswagen Passat and Volvo S40.

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