I suspect you are referring to the substitution of silica for carbon black
in the tire to make the EPA happy.

"Crazy George" wrote in message
...
OK, some of you guys are old enough to remember the answer to this
question.
Used to be a real problem. If no one guesses it, I'll post the science
tomorrow. Geeeeez!!!

--
Crazy George
Remove N O and S P A M imbedded in return address
"John Smith" wrote in message
...
Here's one to explain:

There I was, driving along a two-lane asphalt highway trying to listen
to
an
AM band station on 1230 kHz about 70 miles away (they only run 250
Watts)
and getting considerable static. I noticed that the static diminished
when
I
came to a stop and resumed when I began again. This was not alternator
whine
or spark plug noise--more like white noise. So, I thought, it must be
static
from wind in the antenna or maybe tire-on-roadway static.

Then I hit a section of road with a new 3-week-old layer of asphalt laid
over the old asphalt. The noise disappeared! The noise returned when I
drove
off that new section of asphalt. Hmmmm. Did I just imagine it? So, I
asked
my XYL to pay attention to the station/static when the next opportunity
arrived. Another section of fresh asphalt produced the same thing and
she
can verify it. It happened every time.

Now I ask you... why would I have statickey noise from driving on old
asphalt? Or, maybe the question should be why would fresh asphalt be a
noise
quencher? Or something.


Thanks,
John
KD5YI