Sport-utility vehicles performed poorly in the latest round of rollover tests released on Tuesday, with none winning the government's highest safety rating, Associated Press (AP) reported.

AP said most of 14 2003 model year SUVs tested by the National Highway Traffic Safety Administration got three out of five stars while none received a four- or five-star rollover rating.

That, AP noted, was little improvement over the 2001 model year, when the Pontiac Aztek was the first and only sport-utility vehicle to win an NHTSA four-star rollover rating. In 2002, the Aztek and the Acura MDX earned four stars.
The Cadillac Escalade EXT, the Chevy Avalanche and the Mitsubishi Montero Sport [Challenger] received two-star ratings, AP added.

AP said that SUV rollover ratings became a big issue in the United States this year when NHTSA chief Dr. Jeffrey Runge said at a motor industry conference that he "wouldn't buy my kid a two-star rollover vehicle if it was the last one on Earth."

According to Associated Press, Runge later said he only meant that buyers should be aware of the driver's experience when choosing a vehicle but he has repeatedly expressed concern about SUVs' high rollover rates. More than 60% of fatalities in SUVs involve rollovers, compared to 22% of car deaths, AP added.

However, GM spokesman Jim Schell told AP that NHTSA's rollover ratings are flawed because the agency uses a mathematical formula, based on vehicle height and weight, rather than a moving test to calculate rollover risk. He also told the news agency that NHTSA fails to take into account stability control systems, which are an option on many SUVs.

"GM doesn't feel that this is a good indication of real-world stability," Schell reportedly said.

But NHTSA spokesman Tim Hurd defended the test to Associated Press, reportedly saying the agency believes it is a good predictor of vehicle performance, and adding that NHTSA plans to abandon the mathematical formula later this year in favour of a new, moving test that will show how the vehicle responds to sharp turns.

AP said vehicles did much better in NHTSA's crash test ratings, which also were released on Tuesday. The Chrysler Pacifica, which was the only 2004 model vehicle tested, won five-star safety ratings in all four front- and side-impact crash tests that NHTSA performs while no other SUV won five stars in every test, the report said.

AP noted that the Chrysler Pacifica was not given a rollover rating, adding that Chrysler spokeswoman Angela Ford reportedly said that NHTSA wanted to wait until its new tests were in place before testing the Pacifica.