With the recall nearly 75 percent complete, Bridgestone/Firestone said today that it has surpassed the 4.8 million mark in its safety recall of 6.5 million tires, and that its scientific process to isolate the root cause or causes of accidents associated with a small percentage of its tires is centering on the design of the recalled tires, and the manufacturing process at its Decatur, IL facility. “No one is more interested in finding the answer than we are,” said John T. Lampe, chairman, chief executive officer and president of Bridgestone/Firestone Inc. “Our technical team reports that we are concentrating our efforts on a number of factors, including tire design, the tire’s components and external factors, all of which warrant further examination,” he said. Lampe added that as the company continues to search for the cause or causes, it would provide periodic updates on the status of the company’s internal analysis. Some of the things being investigated are tire design and components, manufacturing variability in Decatur, and vehicle-tire interaction. According to the company’s data, the vast majority of claims on the recalled tires involve a rear tire, and the clear majority of those claims involve the left rear tire. In order to fully understand this phenomenon, the company said it must fully understand how the loading or stress from a vehicle affects the overall strength and performance of the tire. In addition to the company’s own analysis, the examination by Dr. Sanjay Govindjee, the independent materials expert retained by the company, is ongoing.