WASHINGTON (Oct. 2)—The National Highway Traffic Safety Administration has opened a preliminary evaluation into possible tread separations on the Firestone Steeltex R4S and Steeltex A/T tires. NHTSA has received 169 complaints on the tires, including reports of two deaths and 12 injuries, all but two of which were filed since Bridgestone/Firestone Inc. announced its recall of 6.5 million Firestone ATX and Wilderness AT tires Aug. 9. The failures occurred with Steeltex tires mounted on Ford F250 and F350 pickup trucks, Ford Excursions and General Motors Suburbans and G-vans, the agency said. NHTSA began its preliminary evaluation of the ATX and Wilderness tires May 2, and upgraded that investigation to an engineering analysis last month. In a prepared statement, Bridgestone/Firestone said it "will continue to work diligently to fulfill these inquiries in a timely and responsive manner with limited staff and limited resources." A company spokeswoman said the tire maker is still trying to determine how many Steeltex tires are involved in the new investigation.