Citing the findings of a vehicle expert, Bridgestone/Firestone Inc. president & CEO John T. Lampe today requested that the National Highway Traffic Safety Administration (NHTSA) begin an investigation into the safety of certain models of the Ford Explorer.

Lampe said his company’s analysis clearly shows that a substantial segment of Ford Explorers are "defectively designed," putting the driver and passengers at increased risk during routine, foreseeable highway driving maneuvers following events such as a tread separation.

Dennis A. Guenther, professor of mechanical engineering at Ohio State University, conducted the study cited by Lampe. His study shows that in most circumstances, certain models of the Explorer will experience an "oversteer" condition following a tread separation on a rear tire, a clearly foreseeable event.

“An oversteer vehicle is not safe at highway speeds in the hands of an average driver,” Guenther said. “This must be regarded as a highway safety defect within the meaning of NHTSA's charter.”

“When tires fail, either from a tread separation or a road hazard or other causes, drivers should be able to pull over, not rollover,” Lampe said. “The Explorer does not appear to give the driver that margin of safety to make it to the side of the road and change the tire.”