GREENVILLE, S.C. (July 3)—Michelin North America is replacing at no charge as many as 30,000 Phantom A/P brand tires it manufactured for Discount Tire Co./America's Tire Co., although it said the tires aren't defective and it isn't a recall. Michelin initiated the replacement program in 66 U.S. cities, primarily in the Southwest, where about 192,000 Phantom A/P tires were sold. A "fraction of that number may be affected by the extreme use of environmental conditions that can cause them to come out of service before the usable tread is worm," the company said. The action is a precautionary move, a spokeswoman said, and covers tires purchased between January 1997 and December 1999. Buyers have until July 16 to exchange tires.