A niche mentality is common among the leading global suppliers, says John Hoffecker, a managing director at AlixPartners LLP, a suburban Detroit consulting firm. "The companies that succeed tend to distinguish themselves somehow from the competition," says Hoffecker, who has tracked supplier industry trends for the past decade. "I don't mean they create a niche product. But they might carve out a niche in technology or in their ability to work quickly.

"In Magna's case, they're in a business area where not too many people make money. But Magna's strength is in its fabulous execution. Customers are drawn to that. "You see it all over the list," Hoffecker says.

"Continental was just a tire company a few years ago," a reference to the No. 13 supplier. "Now they're really a stability-control company. Had they continued to be only a tire producer, they probably wouldn't have continued growing." Continental added just over $1 billion in original-equipment sales last year. Much of that was revenue from Phoenix AG, a German producer of fluid-handling components and seals that Continental acquired in late 2004.

But rising to the top takes more than being tight with the customer, Hoffecker says. "Moving along with a rapidly growing customer has a risk," he says. "The supplier has to bring something more to the relationship. "Auto companies don't want the risk of relying on suppliers around the world who aren't always innovating and improving. There are too many other suppliers out there who are willing to do that."