Some of Toyota's U.S. plants are now more than 20 years old, and a growing number of its workers are paid the top wage of about $25 an hour. That's less than Detroit's veteran union hands make now, but a contract inked last fall will enable U.S. automakers to replace many highly paid employees with cheaper workers. By 2011, Toyota's cost advantage over Detroit could disappear. "The Japanese automakers have been here for almost 30 years," says Michael Robinet, an analyst at CSM Worldwide, a Northville (Mich.) research firm. "They'll start to have Big Three-like costs creeping in."