I run 80 PSI in my rear tires and the only problem I have had in over 60K
miles has been flats on both rear tires caused by valve stem problems.  Both
times I was told that it was caused by the stems not being High pressure
(these were OEM) ones and the ones they replaced them with were metal.  Well
today I went to buy four new tires and told them I wanted high pressure
valve stems put on.  Their reply was that they only had one valve stem that
they put on and it was a high pressure one. Since I had already learned that
the High pressure stems cost about twice that of the regular stem (and why
put a high cost stem on a regular 35 PSI tire), I asked to see the stem.  It
was a regular all rubber stem.  I chose not to get the tires there and left.
Now my question to the group is this -  is there really an high pressure
valve stem that is all rubber?  The tires are load range E (10 ply rating).
Thanks
P.S. And yes I have weighted the vehicle on a cat scale and it needs the
80PSI.

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