DEARBORN, Mich. (Jan. 17)—Ford Motor Co.'s program to buy back 13.5 million Firestone tires will end March 31 as originally planned, a Ford spokesman said. So far Ford has bought back roughly 9.5 million of the tires, or 72.4 percent. The auto maker informed customers by letter last fall of the program's end date, the spokesman said, and it will buy back "as many as we can" in the 2½ remaining months. Ford's May 22 announcement that it would replace the tires for safety reasons caused the end of its 95-year relationship with Bridgestone/Firestone North American Tire LLC. Bridgestone/Firestone insisted the tires were safe.