But a Washington Post analysis of national and Florida crash statistics shows that the Ford Explorer has a higher rate of tire-related accidents than other sport-utility vehicles â€“ even when the Explorer is equipped with Goodyear tires. The finding suggests that something about the Explorer may be contributing to these accidents, auto analysts said.
James Fell, who retired last year as chief of research at the National Highway Traffic Safety Administration, said the findings give "an indication that there may be a factor with the Ford Explorer beyond the tire issue. It's a first indicator that they may have a stability problem."
Ford and Goodyear Tire & Rubber Co. officials criticized the Post's analysis, saying the number of accidents examined was too small to be meaningful, that the databases don't always accurately identify vehicles and that Explorers should not be compared with the entire universe of sport-utilities, which can range from two-seaters to behemoths.
The Post's analysis of fatal crashes nationally from 1997 to 1999, and a much larger Florida database of fatal and nonfatal crashes for the same period, indicated:
â€¢Explorers equipped with Goodyears had a higher rate of tire-related accidents than other sport-utilities in the nationwide fatal-accident records, though the 2,000 accidents involved are so few that the difference could be a statistical fluke. But an analysis of 25,000 fatal and nonfatal sport-utility accidents with 83 blown tires in Florida shows that tire blowouts in Goodyear-equipped Explorers contributed to crashes at rates more than double those of other sport-utilities. (Explorers with Firestones crashed four times as often as other sport-utilities after tire failures.)
â€¢The Florida data indicated that Explorers were no more likely than other sport-utilities to have brake problems, worn tires or most other equipment failures that contributed to an accident. However, no other make or model of sport-utility has a pattern of equipment failure related as strongly to accidents as the Explorer's tire blowouts. Using two different ways of measuring accident rates, the Explorer was either three times or four times as likely as other sport-utilities to have a tire blowout contribute to an accident.
â€¢Explorer's higher fatality rate in blowout accidents may be related to rollovers. In 5,870 single-vehicle accidents, the Explorer was 13 percent more likely to roll than other compact sport-utilities against which Ford likes to compare the Explorer's rollover record. The Explorer was 53 percent more likely than other compact sport-utilities to roll over when an equipment failure such as faulty brakes, bald tires or blowouts caused an accident. The national data showed that in the 187 blown-tire accidents that killed someone in the sport-utility, the Explorer rolled over 95 percent of the time, compared with 83 percent for other sport-utilities.
Though tire blowouts are rarely the cause of accidents â€“ and Florida is warmer, so its blowout rate may be higher than other states â€“ the differences found in Florida between Explorers and other sport-utilities is statistically "very, very significant," said Hans Joksch, a research scientist from the University of Michigan Transportation Research Institute.
"These are very simple, straightforward analyses that don't look at the fine points, but the results are so strong that it should lead to detailed study to what extent it's the tires, to what extent it's the Explorer, to the extent that it's Firestone and Goodyear," Mr. Joksch said. "The whole issue should be examined much more closely."
Bridgestone/Firestone on Aug. 9 recalled 6.5 million 15-inch Firestone ATX and Wilderness AT tires, which were mostly on Explorers.
Ford has paid $4 million to settle 17 lawsuits triggered by Firestone-equipped Explorer crashes, the company told congressional committees. Firestone has paid $12 million to settle 14 cases. Government officials in Venezuela, where Ford replaced Firestone tires before the U.S. recall, have said Ford and Firestone share responsibility for the 47 deaths and dozens of accidents that have occurred there.