I'll go with this story. I have seen this happen on at least two of my
vehicles.

John Rodgers
88 GL Driver

Bob Mac wrote:

>  I have another theory that you might want to look into. As cars get
>older they go thru many many sets of tires. Over the years the tire man
>that mounts these many sets of tires slaps some type of goo on that is
>supposed to seal the tire to the rim. After a while the tire change
>machine scrapes and gouges the rims where the bead is supposed to seal.
>Rust forms around the bead and little bits of tire bead rubber all stick
>to this goo forming air gaps just big enough to let the air out slowly.
>Next time you have the tires off, sand the rim where the tire seals to
>get all of the chunkies off. Then goo it up and mount the tire. This may
>not be the answer to your problem but it solved a lot of mine. Hope this
>helps.
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