Tire is leaking but nobody cant find from where

One of my tires is ever so slowly leaking air, like 1 PSI per week. It’s Falken AT 275, stock wheels. Im not using the TPMS to assess this. Ive taken it to two shops and they both couldnt find any punctures. One of them even resat the beads and applied lubricant, etc.. but it keeps leaking. Any ideas?

 

Do you have any bends or pinches in the rim? I had this happen to me years ago on a sedan I owned. The rim was bent juuuuust a bit and caused the tire to leak air about 1 or 2psi per month.

You can also check yourself to see if the valve stem is the issue. Spray soapy water on it. if you see bubbles, then you've found the root cause.

 

Shops dont have a simple tire leak tank? Even a 25 gal water trough would be enough to look for the leak.

If the shops did a thorough enough tire check then the next suspect is a crack somewhere on the rim itself.

 

Over pressure tire by 5-10 psi. Make some snoop (1 drop dish soap in a full spray bottle of plain water). Spray it on and watch for tiny bubbles for a good while. Spin tire another 1/4 turn. Go through 4 1/4 turns until you find leak. Also make sure your TPMS is snugly tight and spray around stem and Schrader.

 

And Drive on the soapy tire slowly and have another person watch for bubbles. I had a small sidewall cut that did not present the leak when unloaded.

 

As mentioned above, check for rim leak. Try soapy water. And, check the wheel itself. I had a rock wedge between the wheel and brake caliper, and ended up with a pinhole leak in the wheel itself a few years ago.

 

I had a slow leak that Americas Tire couldn't find. But the tech did notice a little corrosion at the rim on one of my 21 yr old wheels. He cleaned it off (I don't know with what...perhaps a wire brush or steel wool or a scrunge?) and no issues for a few months after that.

 

Agreed, I had a mystery leak once that took 5 trips to the tire guys to figure out. The TPMS sensor had o rings etc that once take apart reconditioned and reinstalled fixed the leak. Never bubbled in the tank or never bubbled when sprayed with soap. It would only leak when centrifugal force was applied while driving.

 

If all else fails have a shop put a know good tire on the "leaky" side's wheel and the "leaky" tire on a known good wheel.

That could help determine if you have wheel or tire trouble...

 

Dunk the wheel/tire.

 

Yeah, Whip that would seem to be the easy way.

I had a new 5 gal corney keg for a home made "malt beverage" that wouldn't hold pressure. I soaped the heck out of it many times. No luck. So I bought a plastic garbage can big enough to submerge the keg. I filled the can w/ water, over pressured the keg and dunked it.

About 15 seconds later I found a pin hole in one of the welds...

 

I had a very similar leak. I eventually found a very small headless nail (brad) that would only leak when the nail was at the 6 o’clock position with the weight of the vehicle on the tire. Suggest you pull the wheel and tire assembly off and take a close look.

 

I had a leaky tire on my CRV that no one could find the leak. Finally they found out my rim was cracked and I had to replace the rim.

 

Maybe tighten the valve stem core a bit (or replace).

 

I had a very slow leak that no one could find. It took me about 20 minutes with the tire off and in my front yard spraying soap water on it. It had been leaking consistently for 3 or so months, I knew I had a leak somewhere.

It ended up being the valve stem had a slight crack in it. You had to move the valve stem slightly for it to start leaking. I took it back to the tire shop and told them where it was, they couldn't find it, so I had to go inside the shop and spray the water on and show them how to "expose" it.

 

I recently had a problem with the TPMS going off daily during a trip to snow country and the same tire needed a little air each time. I suspect the cold weather caused the valve hardware to leak because it hasn't happened since that trip.