The Ford Explorer sport-utility vehicle rolls over more often than other SUV's do in tire-tread accidents, and it has vibration and suspension problems that Ford can't always explain and sometimes can't fix. Those flaws raise the suspicion that the Explorer itself is contributing to the sometimes fatal accidents that forced the Bridgestone/Firestone recall. An internal memo from Ford of Venezuela says that the Explorer "turned over unexpectedly" when Firestone tires lost their treads, but that other SUV's didn't in similar circumstances. About 31% of Explorer complaints cited mysterious vibrations. Many could not be cured, even after dealers changed tires, shock absorbers and drive-shafts. Less frequent is an odd tire-wear pattern called "cupping." It shows up in less than 2% of Explorer complaints, but never shows up in most other Ford truck models.

The Ford Explorer was first offered for sale in March 1990. Ford internal documents show the company engineers recommended changes to the vehicle design after it rolled over in company tests prior to introduction, but other than a few minor changes, the suspension and track width were not changed. Instead, Ford, which sets the specifications for the manufacture of its tires, decided to remove air from the tires, lowering the recommended psi to 26. The Firestone-recommended psi molded into the tire for maximum load is 35psi.

The failures all involved tread separation—the tread peeling off followed often by tire disintegration. If that happened, and the vehicle was running at speed, there was a high likelihood of the vehicle leaving the road and rolling over. Many rollovers cause serious injury and even death; it has been estimated that over 250 deaths and more than 3,000 serious injuries resulted from these failures.

Ford and Firestone have both blamed the other for the failures, which has led to the severing of relations between the two companies. Firestone has claimed that they have found no faults in design nor manufacture, and that failures have been caused by Ford's recommended tire pressure being too low and the Explorer's design. Ford, meanwhile, point out that Goodyear tires to the same specification have a spotless safety record when installed on the Explorer, although an extra liner was included into the Goodyear design after recommendations to that effect were made to Ford. Firestone included an extra liner in its product and this was then also used to replace tires on Ford Explorers.