RE: The tire from hell...

["Rudy Consolacion" <rconsolacion@kumhotech.com>]

Silica is used in place of carbon black in the tread rubber to 
improve wet traction while not increasing rolling resistance. The 
only problem is that silica is not a good conductor and when static 
electricity builds, the tires don't act as a ground to dissipate the 
electrical energy. When you get out of your car, you become the 
grounding device, or if you're driving and pull up to a toll booth, 
the toll booth collector becomes the ground. I've heard of stories 
where toll booth collectors would refuse to collect from certain 
vehicles because of the static shock they would get when handed the 
money. These cars usually had Michelin OE tires. Silica tires have 
also been known to make electronic onboard compass systems 
inaccurate. 

OE manufacturers are aware of this problem and now have specs for 
tire conductivity.  Tire manufacturers are using methods (sorry, 
that's classified info) to improve conductivity while using the same 
silica formulation. Silica is also much more expensive than carbon 
black which means it's mainly used on high-end tires.

Rudy C. 

> Rudy,
>    Thanks for the more technical insight; "Alls I knows is, I like 'em". One
> question, what does your quote, below, mean?
> 
> > -----Original Message-----
> > [SMTP:owner-quattro@coimbra.ans.net]On Behalf Of Rudy Consolacion
> >
> > Michelin and Goodyear have
> > upped the traction ante recently with silica tread compounds. (Be
> > careful to not get shocked when you get out of your car or give your
> > money to the toll booth collector.)
> 
>