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From Michelin, a Pricey New Tire That Survives Blowouts

By Warren Brown
Washington Post Staff Writer
Sunday, October 24, 2004; Page G02

"Peace out" is now possible with a catastrophic tire blowout.

Michelin Corp., the French company that introduced radial tires in 1946, has perfected -- or, at least, has come close to perfecting -- run-flat tires.

Michelin's new tire, currently fitted to the premium Touring edition of the 2005 Honda Odyssey minivan, is the "PAX System."

"Pax" means "peace" in Latin. It refers to a kiss, handshake or other greeting meant to signify friendship.

But on the road, the PAX System could mean the difference between life and death in an accident in which one or more of a vehicle's tires blow out or otherwise deflate quickly, according to engineers at Michelin and at Italy's Pirelli Group, which shares in the development of the PAX technology.

Blowouts frequently lead to loss of driver control over the affected vehicle. An uncontrolled vehicle can roll over, or swerve or skid into a fixed object. At the very least, that kind of tire failure could leave you stranded in a place where you'd rather not be.

In response, tiremakers and automobile manufacturers since the early 1990s have been offering various versions of run-flat tires generally designed to travel for 50 miles at about 50 miles per hour after complete deflation.

Typically, run-flats have narrow, reinforced sidewalls that continue to support a lightweight vehicle, such as a sports car, after losing air pressure. Such tires also have had two big drawbacks.

First, they compromise the quality of a vehicle's ride, turning it into a hard, jolting affair -- especially on less-than-perfect roads. And, second, because of their narrow sidewalls and limited load tolerances, those early-generation run-flats can not be used on the heavier minivans and sport-utility vehicles that most American consumers buy.

The PAX System -- actually a three-in-one tire and wheel combination -- is designed to eliminate those run-flat shortcomings. It does so by actually anchoring the tire to the wheel, as opposed to the traditional method of using the air pressure within the tire to keep it mated to the wheel rim.

When traditional tires, run-flats or others lose air pressure, they eventually twist off, separate from the rim. But the extra stress created on a deflated PAX tire actually causes it to screw more tightly to the rim, according to Michelin and Pirelli engineers. Thus, there is much less of a chance of catastrophic tire separation.

A polyurethane support siding inside the deflated PAX tire keeps it stiff enough to support a minivan or mid-size SUV for up to 125 miles at a suggested speed of 50 miles per hour. But what's critically important here is that the PAX System helps to reduce fatal rollovers of heavier vehicles in tire-blowout incidents, says Edouard Michelin, president and chief executive officer of Michelin.

"We consider it a major development in vehicle safety," as important as the introduction of radials, if not more important, Michelin said after a recent PAX demonstration in Shanghai.

But will consumers buy it?

Honda, at least, is betting that they will, even if it means paying at least $6,000 more to acquire those tires, along with other premium options, in its top-of-the-line 2005 Honda Odyssey Touring minivan.

Minivan drivers value peace of mind, especially when they are transporting children over long distances, says Honda spokesman Andy Boyd. PAX offers them that peace in a premium package, he said.

But, for Honda and other car companies that eventually will offer the PAX System, the tire brings another tangible retail benefit -- customer retention. The PAX tire must be removed and remounted in shops that have the special equipment and trained personnel to handle the job. That means if you buy a PAX-equipped vehicle from a given vehicle maker, you probably will have to return to that manufacturer's dealership to get it serviced.

© 2004 The Washington Post Company