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PAX Run-flat system


Tony
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PAX is an acronym for something, we never was told, needless to say PAX is/was Michelin's attempt to evolve a run-flat tyre system. PAX was fitted to many cars including the Honda Odyssey Minivan Touring Model and the Rolls Royce Phantom. the list is growing. In Europe, a number other manufacturers have adopted the PAX system.

 

So what is it?

This cutout shows the PAX hoop inside the tyre

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The tyre is locked into a special wheel rim configuration that ensures the tyre stays in place even when deflated

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It's component parts

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But there's a problem

Replacing the tyre needed such special machinery no one could change the tyre. Toyota with the Rave 4 opted that you need to replace the tyre and wheel when a tyre was needed.

 

 

In the real world

To replace the tyre you need one of these, the BOSS

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A replacement Michelin PAX tyre, if you can work out the size your better than us......

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Plus the PAX tyre fitting kit

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Removing the tyre

Why do we need the BOSS.... The beads on the Michelin PAX tyre are incredibly flexible so a conventional fitting machine cannot rely on the side-walls rigidity to pull the tyre bead away from the rim. The BOSS needs to manoeuvre the bead-braker in two dimensions. Reason for this is the rim has a step the tyre needs to ride up and over

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Once the outer bead is removed the inner arm on the BOSS can push the PAX off the conical wheel

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Now we have the odd design of wheel in full view

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The replacement tyre

The new tyre comes with a cooling gel, this does what it says on the tin and keeps the tyre cool when running flat, needless to say we have to apply the gel

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Now the hard part

After the back bead is fitted the PAX hoop is reinstalled

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Once in place the BOSS's powerful hydrolic's is used to press the PAX onto it's conical position on the wheel, this uses immense pressure

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Lastly the tyre beads need to be manipulated to the rim, by using tools supplied with the tyre

post-2-1292447589.jpg

 

Once done it's inflate time

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Job done

One tyre, one hour :lol:

 

This particular car was from a main dealer, even they cannot fit tyres to their customers cars, tyre evolution really can be the chicken and the egg scenario sometimes :lol:

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Wow that's quite an involved process then! Is the PAX system still used then? I thought other than cars that already have it that not many manufacturers (if any) still use it due to the complexity.

 

Looking at the tyre though and the way it rides on that block in the centre of the wheel when flat, does the PAX work better everyday in terms of ride comfort and handling because the sidewalls don't need to be super stiff?

 

I'm guessing though that replacing a PAX tyre costs quite a bit more than replacing a normal tyre?

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Wow that's quite an involved process then! Is the PAX system still used then? I thought other than cars that already have it that not many manufacturers (if any) still use it due to the complexity.

 

Looking at the tyre though and the way it rides on that block in the centre of the wheel when flat, does the PAX work better everyday in terms of ride comfort and handling because the sidewalls don't need to be super stiff?

 

I'm guessing though that replacing a PAX tyre costs quite a bit more than replacing a normal tyre?

 

PAX still exists and may get stronger since the RFT is despised, fitting the PAX adds around £70 to the tyre cost, which compared to the RFT is still a great saving.

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I thought the PAX system had bit the dust, after the class action in the States.

 

Business News

 

By failing to see the product through the lens of the customers' total experience, Michelin's hoped-for killer competitive advantage limped along until April, 2008, when the company announced that it would discontinue the line.

 

From reports on the Class Action

 

A major tire manufacturer and car company have settled a nationwide class-action lawsuit brought by consumers who claimed they were misled about the benefits of their "run-flat" tires and were then further burdened by the slow and expensive repair process.

 

In their 140-page consolidated amended complaint filed in May, the plaintiffs allege Michelin, which made the tires, and Honda, which outfitted certain cars and minivans with Michelin's PAX Tire and Wheel Assembly System, failed to disclose that the tires last half as long as radial tires. They also alleged the tires are "prohibitively expensive to repair and replace" and that sufficient repair facilities and stock of the tires and other parts of the PAX system do not exist in the U.S.

 

According to the suit, the paucity of repair facilities, exacerbated by the system's discontinuation, has led to inconvenience and poses a safety risk for those who must drive on bad tires.

 

HighlandPete

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I guess that action is just in the states ( looks like they finished with them in 2008 ), so we Brits continue to suffer. Seems they have been fitted to quite a few makes:

 

In Europe

 

* Bugatti Veyron EB 16.4

* Renault Scenic models in Europe—introduced in February 2002

* Audi A8 in Europe—introduced in November 2002

* Rolls Royce Phantom -- introduced in January 2003

* Audi A4 in Europe—introduced in September 2004

* Honda Odyssey -- introduced in September 2004

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Wow that's quite an involved process then! Is the PAX system still used then? I thought other than cars that already have it that not many manufacturers (if any) still use it due to the complexity.

 

Looking at the tyre though and the way it rides on that block in the centre of the wheel when flat, does the PAX work better everyday in terms of ride comfort and handling because the sidewalls don't need to be super stiff?

 

I'm guessing though that replacing a PAX tyre costs quite a bit more than replacing a normal tyre?

 

PAX still exists and may get stronger since the RFT is despised, fitting the PAX adds around £70 to the tyre cost, which compared to the RFT is still a great saving.

 

How much weight does this system add compared to normal or run flat tyres on normal alloys?

 

Also what happens if you need a replacement tyre when you have a quick weekend trip to Monaco and need that new tyre before you head home?

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  • 11 years later...

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