I have a 18x8x5 chrome wheel on a 225/40/18.My old tire got a flat so I took it to a used tire shop and got a good tire, and the same day it started leaking air. Got them to replace the tire and the same day the tire went flat again. Took it back they added some more sealant and it has been good for a few days now, it has started leaking air again.I read that the sealant can come off because of a dirty rim?What can it be It's not bent.
Low profile tires

 

First off it's a used tire shop so that is never necessarily good. You definitely need to clean the wheel, get a "good" tire, soak it well when mounting the new tire and hope for the best.

 

Sounds like wheels are corroded inside thats why its not sealing. Time for new wheels. The correct tire size for 18x8.5 would be 235 or 245. Low profile tires would be 35 and below.

 

Thanks everyone.

 

also chrome wheel over time may get micro cracks from the stress of usage so applying sealant may not work over time i went threw the same thing back in the days of bling bling and they all where gettting the same issue just food for thought

 

Yea I bought the car with the wheels.I'm not a fan of chrome.Gotta find me some nice 19s

 

So it would be a 235/40/18 or 235/35/18?

 

If no cracks check or clean and change the valve stem!

 

I was gonna say valve stem, my tire kept going flat, took it off a few times cleaned etc. Third time found it was just a bad valve stem

 

Clean the wheel and try bead sealer.

 

I had this problem with my OEM wheels. There was a lot of corrosion. I had them sandblasted and powdercoated. No problems since.

 

I say valve stem myself because this happened to my Volk GTC's... My wheel guy took out the valve stem and cleaned it with rolled up sand paper then reinstalled and bam no more leaks....