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How Self-regenerating Tire Tread Works

        Auto | Wheels

Michelin's XDA5 Tire
Semi-trucks like these are the best candidates for regenerating tires, because they have many tires and replacing them can be very costly.
Semi-trucks like these are the best candidates for regenerating tires, because they have many tires and replacing them can be very costly.
­©­­ Tremblay

To most car owners, 300,000 miles may seem like a huge amount to put on your vehicle's odometer, but for 18-wheeler trucks, that kind of distance is business as usual. It's also happens to be just about how long their tires typically last

[source: Brown].

These trucks can cover 1,000 miles (1,609.3 kilometers) in a single day and carry tremendous amounts of weight wherever they go. They're equipped with special, heavy-duty tires, but of course, those tires aren't immune to the laws of physics, either. The tires wear down over time just like yours do, and the cost of replacing tires adds up for trucking companies -- remember, they also have to pay the cost of running behind schedule while the tires are being replaced.

In 2007, tire manufacturer Michelin announced a new solution to the problem of tire life on big rigs. Their XDA5 tire is designed to give truck tires a 30 percent longer lifespan through the use of regenerative tread technology. Sounds awesome, but how does it really work? Essentially, as the tire wears down, the tread reveals new grooves and tread blocks. Once one set of tread has been worn away, a new layer arrives on the surface from underneath the worn out layer [source: Michelin]. The tread on modern tires is comprised of interlocking blocks of rubber. Michelin's XDA5 tires are molded with grooves concealed deep inside those tread blocks. The new grooves are exposed once the tire is about two-thirds of the way worn out.

Does the tire itself regenerate? Not really. But once the grooves that are vital to traction in rain and snow are depleted, a new layer pops up, providing proper grip until a new set of tires can be installed. The tires still get worn out, but they have new grooves, which mean they last longer.

The tires also contain technology called raindrop grooves -- sipes situated deep inside the tire that are designed to channel water on the road surface to the left and to the right, away from the bottom of the tire. This prevents slippery buildup underneath the tires. When the tread becomes worn, the channels gradually open to create new sipes in the middle of the tread block. Michelin says it uses a patented manufacturing technique to mold the XDA5 tires in three dimensions, creating grooves that exist underneath the surface of the rubber.

In the next section -- is 30 percent longer life really worth it? What are the benefits of self-regenerating tire tread? And will you be putting these tires on your family sedan anytime soon?