Michelin PAX System
The core of Michelin's PAX system is the semi-rigid ring installed onto the rim using special equipment.
The heavier sidewalls and special bead construction allowed a driver to drive a car with little or no air pressure at a limited speed (approximately 50 mph) over some specified distance to a service station, or at least off the roadway out of immediate danger.
The reinforced sidewall Goodyear EMT (Extended Mobility Tire) was introduced with the 1994 Chevrolet Corvette.
This low or no-pressure condition was almost impossible to detect by the driver with a zero pressure run flat, until the tire failed.
When flat, the PAX tire sidewalls collapse until the weight of the car is riding on an internal polymer support ring mounted to an asymmetric wheel.
The inner support ring is also coated with a gel that is required to lubricate the rotating flat PAX tire.
[citation needed] Michelin also worked with Honda (for the Odyssey minivan) and Acura (for the RL luxury sedan) to ensure each dealer carried a full set of replacements wheel tire combinations in inventory.
By licensing the PAX technology to other companies, Michelin would ensure that the consumer would not be locked into a single supplier as with the TRX.
Pirelli,[3] Goodyear,[4] Toyo[5] and Sumitomo[6] have licensed the technology from Michelin, but these companies never came out with PAX system tires.
In December 2007, Michelin announced that it would halt further development of the PAX tire,[7] but would still produce them for the foreseeable future, essentially a repeat of the TRX scenario.
A class-action suit against American Honda Motor Company involving the use of Michelin PAX tires was settled in December 2008.
[9] It appears that the major impetus for the class action was the poor tread-wear performance of the PAX tire on the Touring Edition of the third-generation Honda Odyssey minivan built for the North American market.
Certain models of the Acura RL were equipped with higher-performance PAX system Michelin Pilot HX MM4 tires.
