e-man

Hey guys. Both of my left side tires seem to lose about 1-2 pounds of air pressure every week. I usually try to keep all tires at around 35 psi, and, within about a month, the left side tires are at 28 psi (while the right side remain at 35). During a recent oil change, I had Lexus do a visual inspection for nails, screws, etc., and they didn't find any. Does anyone know what might be causing this? It's not a huge deal, but it's a little annoying that I have to keep filling them up with air every few weeks. By the way, the tires are Toyo Proxes4 with about 12,000 miles on them. Thanks.

e-man

Johnny Mo

1) Chrome rims? If you have them you need to check the bead...sometimes the chrome starts peeling, and causes leakage at the bead, or valve stem.

2) valve stems, if they are the metal "bolt" in type, then you'll need to check that they are tightend properly, and not loose OR over tightened.

3) could be a bad valvestem core

4) also very important to check the air pressure cold...if you check it after a ride - even a short one, the air will heat up and expand, so the next time you check it will be different.

If it's not any of that - it is possible the tires didn't seat properly - but you'd see it and it would most likely pop into place from driving.

Other than that I have no other clues.

e-man

Good questions. I should have been more specific. I have stock 17" non-chrome rims. I'm not sure about the valve stems, but they look to be pretty normal (if that makes sense). As for the cold/hot issue, I check them when they are cold and hot, and the variance is usually 1-2 pounds. However, I am comparing them to the 2 that don't leak, so I'm pretty sure that the loss of 7-8 pounds over the course of a month is due to a leak and not due to the fact that they're cold (especially because the right side tires are staying pretty close to 35 psi over that same period of time). How do you know if a valve stem has been overtightened or not tightened enough? Not to sound like a total moron, but I didn't even know that valve stems were supposed to be tightened. I thought they were just mounted in there somehow (and now I am sounding like a moron).

e

chuckb

just take it to a reputable tire shop e. they can find where they are leaking for pretty cheap.

Brandon@TR

You can always dunk the tire and see if any air is leaking.

Benjamin T

iTrader: (2)

yeah... find a big container, fill it up with water, dump the wheel and tire in and start looking for bubbles.

the 2 slow leaks i've had in my lifetime was 1)bent pin in valve stem 2)tire shop did not clean wheel lip properly before mounting tire.