I've got Toyo Proxes 4, 215/35/18's sitting on HPD Pypz with 15k miles on them.

I've got a slow leak in my left front tire. I took it to a tire repair shop, and they said they couldn't find the leak. To prove it to me, they put 50psi in the tire, and marked a chalk line across the treads, and slowly rotated the bottom half of the tire under water. No bubbles from anywhere. I'd assume 50psi would push out somewhere, in a 35psi tire...

That was two days ago, and my tire monitor popped on again today. I havn't verified the PSI, but the front left feels a bit squishy-er than the other 3 (made a fist, and push on the tire with my thumb).

The first time the tire monitor went off was Friday, and I reset it and it didn't pop back on until Saturday. I reset it, and it stayed off until Monday. I reset it and thinking I had a glitch in my system I didn't get it checked out. Wednesday rolls around and it pops on, so after I park at work I look at the tire and am amazed to find it has lost over HALF of it's air. Amazed mostly because I didn't notice any difference in driving to work... Obviously I don't drive spiriting during my commute, otherwise the tire may have fallen off the wheel.

So I pumped the tire back up using a pump at my parking garage, and took it to the tire repair guys who couldn't find the leak. I shrugged that off as well as a fluke... Maybe I took a corner too hard which started a slow leak, and once it lost enough pressure it couldn't keep a seal or blah blah blah...

Anyhow, it's pretty apparent there's a leak now. But 50psi and submersion didn't fix it. I could just spray puncture seal in there, but I don't think thats a good option. Suggestions?

 

My wife in a chemist at Firestone. Tires are the most important part of a cars safety, handling, ride, etc. and did I mention safety. Do not mess around with this situation, have this tire dismounted and inspected, have the rim of your wheel checked as well. If the tire has been run with low pressure(15 psi) for even one mile, the inner liner(seal the air in) or the sidewall contruction can have been compromised.

Please all drivers check your air pressures, do not trust the pressure warning systems alone. If your low pressure light does comes on, check the pressures of all your tires, before just reseting your light.

I have gotten out of my Mini countless times at red lights to tell people that they have a tire that is going flat. Please check your air pressures.

 

I had a similar problem like this that drove me nuts and it ended up being an issue with the valve stem. Les Schwab couldnt find a puncture or leak, but one night it was raining really hard and I was checking the tire and could hear the leak from the stem gurgling in the rain. If I fiddled with it, it stopped. I think if I pushed it up it leaked, and down it didn't. I took it back in and told them it was the valve stem and they fixed it quickly for free. So check your valve stem.

 

^ +1 get new valve stems when you have the tire removed and inspected.

 

They did check the valve stem while it was under water. I forgot to mention that. They pushed, pulled, and twisted while I visibly watched, and they even removed the cap and did it again.

I supposed getting a new stem put on there anyhow wouldn't hurt.

 

You can put a new valve core in yourself to see if it works.

Try testing it again with it on the car, fill to pressure and put soapy water on the valve and see what happens. If it's worse when it's cold, you may just have to tighten the core.


Is it possible that someone is letting the air out of your tire? Yell at any local kids lately?

 

No I haven't.

It is possible... I've not had any problems since last week, and I never got around to changing anything. Very odd. I'm quite paranoid about it now as well.

 

I had a similar issue on my BBS and it was the wheel itself....it needed to be cleaned. The tire bead wasn't sealing properly and would lose air while driving (not static in a water trough to look for bubbles). Solution was to dismount the tire, clean the rim bead and remount and balance. The shop only charged me $20 to take care of it....fair price.

whatever you do....don't use the seal puncture stuff....might as well pitch the tire and start over as the shop will charge you that much to clean it.