One sizzling day last summer, Mabel and Rafael Valdes packed their two daughters and Mabel's grandmother into the family's Ford Explorer and headed down Highway I-75 for the 2-hr. drive from Coral Gables to Naples, Fla. But on the way, according to Mabel and her attorney, the tread tore loose--"like peeling a banana," says Mabel--from one of the Explorer's rear Firestone tires, causing the sport-utility vehicle to spin out of control, slam into a guardrail and flip over. The accident badly injured Valdes and her family and left her grandmother dead.
It was thus with a sense of relief mixed with...