SAN DIEGO—Poor maintenance, not tire defects, caused blowouts and fires among Firestone tires on San Diego Transit buses, a consultant hired by San Diego Transit has determined.
But his conclusions don't get Bridgestone/Firestone Inc. off the hook, according to a San Diego Transit spokeswoman. The Nashville, Tenn.-based tire maker had a total service contract with the city which made it responsible for maintaining as well as supplying the tires.
San Diego Transit President Ron Yagura canceled the $550,000 contract with BFS last December, after a number of tire-related incidents. These included tire explosions which incinerated three separate San Diego Transit buses at a cost of $429,000.
Harold Herzlich, a Reno, Nev.-based consultant who also serves as a technical adviser to Rubber & Plastics News, a sister publication of Tire Business, was hired to investigate the tire problems in November. The wreckage from the accidents showed "improper and inadequate inflation pressures on the tires," he said.
There also was evidence of friction between dual tires that rubbed together, and of overheated brakes, according to Mr. Herzlich. His findings were pretty much what San Diego Transit expected, according to the company's spokeswoman.
"Based on the leasing of the tires, despite new servicers, the tires would remain on the buses," she said. "We wanted to make sure there were no quality issues with the tires."
San Diego Transit leased about 2,000 tires from Bridgestone/Firestone.
Transit officials are negotiating contracts with Goodyear and Michelin North America Inc. A Bridgestone/Firestone spokesman said he knew of the San Diego Transit study, but had no comment.