RE: [VAL] blowouts

["dtidmore" <dtidmore@xxxxxxx>]

Dave,
I am curious if the tire dealer installed rubber or metal valve stems on
your tires?  We have an '02 19' Bambi that also runs on ST load range D
tires and per Airstream and Goodyear, the tires should be run at 65PSI to
support the load of our rig.  Given the rating that you are quoting (2540#s
each), I suspect that you are also running at 65PSI.  Rubber stems typically
used by tire stores have a max rating of 65PSI, giving no margin for safety.
There have been several other A/S owners that have had the same experience
(ie tire blowout caused by valve stem failure).  When a tire blows, few
people think to see if the stem failed causing the actual deflation.  After
I had a valve stem fail (caught it within seconds and it was obvious that
the stem had failed), I not only switched to metal stems rated at 150PSI,
but installed pressure monitoring.  I can now see that with 65PSI cold
inflation, the pressure builds to 71-72PSI at highway speeds, so if
65PSIrate rubber stems are present, they are over their max rating.  Rubber
stems on tires running 50PSI or so are not a problem, but with 65PSI tire
pressures, metal stems should be installed. The metal stems only cost about
$2 apiece but they do require that the tires be removed from the rim for
installation.  Regardless, metal stems are a cheap piece of insurance in my
book.

David Tidmore
WBCCI 7548