They don't kick him out, lock horns, or have words--although Ron Harbour certainly gives them plenty of reasons. He reminds his hosts that of all the automotive stamping plants in the country, this one, General Motors' Flint Metal Center, in Flint, Michigan, has been among the least productive and most inefficient in recent years. He tells them that some people still consider Flint the "armpit of GM." He recalls that the last time he was here, following the infamous 1998 strike, workers and management barely acknowledged one another. In terms of lean manufacturing, he says, GM is in "sixth or seventh grade" compared with Toyota.

The Flint folks listen but don't flinch. Not the cigar-wielding head of manufacturing, in a black turtleneck, who is accompanying Harbour on a group tour of the plant. Not the 145-plus employees who have crammed into an auditorium to hear Harbour's assessment of the operation and the industry.

It's hard to believe that this is the same company that denied and dismissed similar criticism years earlier from Jim Harbour, Ron's father. But that's how far Harbour and Associates, and its renowned Harbour Report, has come since 1981, when former automotive executive Jim Harbour first tried to rouse a slumbering industry. For years, he was regarded as a pariah, and his brutal assessment of U.S. automakers was considered blasphemy.

Now GM--and the entire auto industry, for that matter--wants to hear what Harbour and Associates has to say. American auto-makers are in a fight for their lives; their Japanese rivals are more productive and more profitable, and Detroit's slice of the U.S. market continues to shrink. In an ever more competitive industry, U.S. automakers are desperate to cut costs and improve plant efficiency--the very things Harbour studies. And that has brought Harbour in from the cold, transforming the little firm from an anathema to a highly influential and respected critic.

The Harbour Report has become the definitive annual study on the state of the automotive industry in North America. It does for manufacturing efficiency what J.D. Power and Associates' ratings do for vehicle quality. As the gray paperback cover promises, the Harbour Report offers "manufacturing analysis company by company, plant by plant." Every summer, the study discloses the sort of nitty-gritty stats that companies ordinarily keep to themselves--the good, the bad, the truly embarrassing.

Last year, for instance, Harbour reported that Nissan's car factory in Smyrna, Tennessee, was the top assembly plant in North America in 2002. On average, its employees assembled a car in just 15.74 labor hours. That's nearly 20 hours less than it took workers at DaimlerChrysler's plant in Toluca, Mexico, which came in 33rd out of 37. Nissan made $2,069 in profit per car, more than any other company. GM managed just $701; DaimlerChrysler squeezed out $226; and Ford sucked everyone's tailpipe, losing $114 per vehicle. Overall, though, GM did make progress, narrowing its productivity gap with Japanese automakers.

The report goes on like this for 242 pages, with dozens of charts, graphs, and tables. It ranks plants by "hits per labor hour" (the number of times a press strikes a sheet of metal). It ranks them according to how long it takes workers to change a die. It chronicles which transmission plants use in-house pistons, oil pumps, and flywheels, as opposed to those purchased elsewhere.