In September 2000 Firestone hired civil engineering professor Sanjay Govindjee to conduct a study into why so many Firestone Wilderness AT and ATX tires were failing. Such failures have lead to catastrophic accidents in which almost 200 people have died. Govindjee recently released his report in which he found no one factor solely responsible for the failures. Instead, Govindjee claims that weather, speed, the tire's design, tire inflation and weight of the vehicle all play crucial roles in tire lifespan. Govindjee did note that of the factors listed, vehicle weight is likely the most important. The report states that cracks grow between the two steel belts, made worse by the heavy weight of the Ford Explorer.

Ford denies that the weight of the Explorer is the primary cause of the tire failures, claiming that the vehicle's weight is well within recognized thresholds. "Our view is that the tire is unduly sensitive," says Ford spokesman Ken Zino. However, the 2002 Explorer will come equipped with larger tires Ford says, raising doubts about Ford's confidence in smaller tires. Additionally, Ford originally recommended that Explorer owners fill their tires to 26 pounds per inch. Firestone maintains that 30 pounds is more appropriate and that the lower pressure contributed to the tire failures. Recently Ford abandoned the 26 pound per inch recommendation and adopted Firestone's 30 pound inflation level. The lower a tire's pressure, the more rubber meets the road causing more friction. This additional friction causes the tire to heat up and heat, according to professor Govindjee, breaks down the tire more rapidly.

Of great concern to Firestone was professor Govindjee's discovery that the problems with Wilderness AT tires likely reach well beyond the 6.5 million recalled in August 2000. The tires subject to the September recall were manufactured at Firestone's Decatur, Illinois facility. Govindjee's report found that Wilderness AT tires manufactured at other Firestone facilities failed at a similar rate as those produced in Decatur. "This means that the [other] tires were equally problematic regardless of the plant in which they were manufactured, and that all Wilderness AT tires could crack and separate," said Joan Claybrook, who heads Public Citizen, a Washington-based watchdog group.