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Slow leak in new tire, just like in old tire

For about the last 6 months, about every 2 weeks my tire pressure monitor would indicate that the right rear tire needs air. I would use a pressure gauge to verify that the pressure was low, and then fill it to the specified pressure. Everything would then be fine for about 2 weeks, when the process would repeat all over again. I took it to the shop but the mechanics were unable to find any slow leaks.

I recently bought 4 new tires, and about 2 weeks later – you guessed it – the pressure in the right rear tire was low again.

My wife believes that she caused the problem by driving on a flat tire about a year ago to take it to the repair shop. I know that driving on flat tire can cause wheel damage, but is there any type of wheel damage that would cause a brand new tire to have a slow leak? Any other ideas (besides a coincidence that the new tire placed on the right rear happened to also have a slow leak)? thanks

If the vehicle has alloy wheels, has anyone checked for a leak in the right rear wheel?

Tester

Was the valve stem replaced? There was a batch of bad ones in the years past.

You don’t replace the valve stems when a vehicle is equipped with a TPMS.

Tester

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Certainly a good shop can find the leak, I am not into day to day car repair of newer vehicles, so my thought of a valve stem gone bad as a possibility was not taking into consideration valve stems are not typically replaced these days, but it is not excluded as a possibility. (Private to tester, did not read close enough that you had moved out of Duluth, apologies for message)

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The air has to be going somewhere. Putting the wheel in a tank big enough to cover it with water should show bubbles forming at any leak spot.

" is there any type of wheel damage that would cause a brand new tire to have a slow leak?"

Damage to the rim could affect the bead sealing properly, and the metal parts of the wheel itself can leak. Either of those problems can often be fixed.

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Do you have chromed rims?

The tire that’s losing air . . . does the rim show any damage, such as chunks missing from a curb strike? It happens, don’t take my question as an insult. That was not my intention

How old is the vehicle?

Can you take pictures of the rim and post them?

Mine were replaced on a recall. Possible cracking stems. I had no problems. When it was being done I complained of parking brake not properly holding. It was adjusted by dealer. No charge.

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I’m guessing the aluminum wheel is deteriorating, that there is some pitting in the surface of the wheel where the tire seals up against it (the “bead”). A slow leak like that doesn’t always show up in a dunk tank unless you’re very patient and have good eyes. But a soapy solution sprayed on the bead and watched carefully might show a leak.

There are places that can repair a wheel like that for about $100, far less than it would cost to replace it.

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I sort of agree and sort of disagree.

[Rant} Many tire shop folks will only take enough time to find obvious leaks in a dunk tank. The ones that require more time? SOL.

I have found that a soapy solution sprayed on the tire also requires more time and a good eye - and even then some leaks will be missed. (Don’t ask how I know) [/Rant]

Thanks for the suggestions. It does seem that wheel damage (or a bad
TPMS) could explain why the slow leak continues even after installing a
brand new tire. I will take the car back to the tire shop to see what
they can find.

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Did the shop inspect the rim for damage before mounting the new tire?
Do you know what the cause of the first flat tire was?

Until this is fixed, you should be keeping the tire topped off to the correct pressure and not waiting until it gets low enough to trigger the TPMS.

Yes, and that’s why I requested you to post a picture of your rim :slight_smile:

Someone who’s willing to be patient will figure this out. That air is escaping somewhere, and bubbles will show up.

If it’s the valve, replace it ASAP. It’s the only part of a modern tubeless tire setup that can totally fail on its own, without some type of impact. If that valve fails, you will have a situation like a blowout in a tube type tire, and it will be easy to lose control.

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Short of horrible luck with flats, I would suspect the TPMS sensor on that particular corner and then possibly the rim itself. The folks above talking about the “valve” and “Stem” can still be correct. The TPMS sensor and valve stem are all in one in that type of car (sensor based TPMS). Maybe it is faulty. Given that it is now the season where temps drop to cold, I’d also want to know how much lower than the rest the one in question was. When the temps drop, one wheel will always alarm first. Maybe it is just that one? You seem to think it is low compared to the rest though, so that line of thinking may be false. If my cold weather idea is unclear here is what I mean.

It’s your wheel. I’d bet money on it