Safety Agency Adopts New Car Rollover Test
The National Highway Traffic Safety Administration unveiled a new test procedure Wednesday designed to provide a realistic evaluation of the propensity of cars and light trucks to roll over in high-speed maneuvering.
The move was cheered by Consumers Union, which has raised concerns about vehicle rollovers, especially among the popular sport-utility vehicles and other light trucks that now make up half of U.S. new-vehicle sales. Previously, NHTSA has concentrated on crash-worthiness, which involves a different type of testing.
The kind of on-the-road rollovers NHTSA is concerned about account for about 10% of the 227,000 vehicle rollover accidents reported in the U.S. each year, the agency said. The other rollovers involve cars and trucks that have left the road.
Wednesday’s report indicates that the
agency “is finally conducting serious research on the SUV rollover problem,” said R. David Pittle, technical director for Consumers Union, which has conducted rollover tests of its own for decades.
The nonprofit organization, publisher of Consumer Reports magazine, is being sued by two auto companies--Brea-based American Suzuki Motor Corp. and American Isuzu Motors Inc. of Cerritos--over reviews that said the Suzuki Samurai and Isuzu Rodeo SUVs were more likely than other sport-utilities to roll over in certain conditions.
NHTSA said it is considering including a rating of vehicles’ rollover propensity as part of its New Car Assessment Program, which ranks vehicles according to their level of safety.
Tim Hurd, a spokesman for the agency, cautioned that the new test is just one step in a continuing effort to develop a consistent method of measuring rollover tendencies.
The results should not be used to evaluate the relative safety of the dozen cars, trucks and vans sampled, Hurd said.
In the test, Ford Motor Co.’s Ranger compact pickup and General Motors Corp.’s Chevrolet Tracker mini-SUV demonstrated “major two-wheel lift” in hard-cornering situations, NHTSA reported. The Ranger lifted two tires off the ground when it was thrown into a J-turn at 52 mph with no braking action. In the same test, Chevrolet’s S-10 compact pickup kept all four wheels on the ground and Ford’s Explorer mid-size SUV demonstrated only minor wheel lift--a situation that test engineers blamed on a faulty anti-lock brake system rather than on inherent instability. Except for the 1997 Ranger, all the vehicles tested were 1998 models.
GM, which builds the Tracker under license from Suzuki--it is a rebadged version of the Suzuki Sidekick--challenged the methodology behind the NHTSA tests. The problem of rollovers is linked to driver behavior, not to vehicle design flaws, the auto maker said.
“The dynamic driving maneuvers they use have some significant limitations to predict real-world rollover likelihood,” GM spokesman Greg Martin said.
At Ford, spokeswoman Jennifer Flake said that “some of the findings are not consistent with what we have found in nearly two decades” of testing the Ranger. But Ford received the study results only Wednesday and was still evaluating them, she said, noting that the company intends to “work with NHTSA to see why the inconsistencies existed.”
One issue is that the vehicles in the NHTSA test were equipped with outriggers--devices used to prevent them from tipping all the way over. It is not known how or whether the devices, which affect a vehicle’s weight and center of gravity, might influence rollover test results.
Suzuki, which has been a focal point of the rollover issue since Consumer Reports savaged the Samurai in a 1988 review, declined to comment Wednesday. The company is suing Consumers Union for product defamation and has claimed that test drivers in 1988 had to push the vehicle well past reasonable limits to get it to tip.
On Wednesday, the consumer group said it believes that pushing vehicles to the limit is the only way to determine how stable they will be in a real-world emergency.
Among other vehicles in the NHTSA test, the Chevrolet Lumina sedan demonstrated minor tilting in the J-turn and the Ford E-150 Club Wagon full-size van, the Chevrolet Astro minivan and the Chevrolet Tahoe full-size SUV demonstrated minor tilting in other maneuvers.
Vehicles that did not tilt in any of the tests were Chevrolet’s Metro subcompact car and C-1500 full-size pickup and DaimlerChrysler’s Dodge Neon coupe and Dodge Caravan minivan.
