SD45-2

I have an 2001 C5 and my right rear tire gets low on air in about 10 - 14 days, I took it up to a reputable tire place and they said they couldn’t find anything wrong with it, even after submerging the tire under water. They said it could be leaking from the valve stem / censor, has anyone ever heard of that before?

roscoe118

Yes, the O-ring seal at the base of the stem has been known to leak. I had one doing the same thing, and had the o-ring replaced when I had new tires installed. It fixed the problem.

I don't know the part number off of top of my head. I called that parts department at the local Chevy dealer and they said you couldn't buy just to o-ring, but someone here listed the part number and I was able to get one. Hopefully, someone will chime in with the correct part number.

You can also use a #9 rubber washer from Home Depot

You might want to have this moved to the Tech section.

HummelS

Works like a champ...

edensknight

Also, one of the metal inner valve stem cores was leaking (faulty) in my left rear, and, I had the inner core replaced (they are easily replaced and merely screwed in with a small and specialized plier at any tire servicer).

ArmyVette

If you have a neighbor with a kiddy pool, remove the tire and dunk it, looking for bubbles.

If you don't have that, make up some very soapy water and apply it to the value stem and where the tire and wheel meet, again looking for bubbles.

HTH.

Vetteman Jack

roscoe is right - the o-rings can leak if not seated properly or if they are just worn. That would be where I would check first if nothing else is readily apparent.

Geno94

Wouldn't submerging the tire and wheel show valve/stem/o-ring leakage also if it was there?

Y2K Corvette

i bought the valve stem seals at my local Chevy dealer, about $2.00 apiece

DeeGee

If that fails mine leaked around the balance weight. It was pinching the bead and causing a leak. Took the tire guy 2 goes to find it.

ORANGEBROTHERS

remove the orings altogether and get some of those real nice c5 flag caps.

SD45-2

I took it to a GOOD tire shop, been in buisness for years. They also couldn't find the leak after submerging it in water for about an hour (I was there also). He then said we'll put nitrogen in the tire, the molecular structure of nitrogen has larger molecules than air and if there's a small leak, it will stop it. It also doesn't make your tire expand when it gets hot or contract when it gets cold, it will maintain what ever pressure you put in it. He said eventualy ALL tire shops will use nitrogen for inflating tires. If there's a tiny leak, he said it should maintain the pressure for at least 3 months. If it goes flat after that, I guess I'll buy a #9 o-ring or just replace the valve stem in itself.

DeeGee

Best of luck

I had Nitrogen in mine after the fit. Costco uses Nitrogen for inflation. It still didn't stop the leak until they found where the balance weight was pinching and replaced it.