Intermittent loss of tire pressure in one tire

This has me perplexed.

One of my relatively low milage (3000 mi) tires loses air pressure intermittently - every 5 months or so I will go out and the tire will be almost flat - over a short time period ( i.e. a day) it loses pressure to the point it is flat. I'll pump it up and it will be fine for another few months - and then suddenly it is flat again. I had the garage rotate the tires last spring and they checked the tire - no nails etc and replaced the valve stem. The only difference after rotation is that the tire leaking is now on the back!

Nothing special about the car or the tires - standard Mercury Mystic Sport

The car is in a garage, so it is not kids.

Suggestions?

Reply to
020SHC
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When mine do that, it is a rim leak. It goes down 'very' slow to a certain point, then the tire against the rime pressure is lower and you park wrong and it drops overnight.

The garage can almost never find these because they blow the tire up hard to test it so the leak gets sealed. If they put it in their water tank with only 10 psi, they would have a better chance of nailing it.

I usually just tell them to dismount it and clean it 'if' they cannot 'find the leak'. The last place argued with me until I got the manager. he was more than happy to take my money and clean the sucker. It was

-30 out and I have 30 psi in the tire. They test it at 40 psi in 75 F temps...

Thankfully those Aluminum rims went to the rust pile with the rest of that Jeep.

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's - Gone to the rust pile... Canadian Off Road Trips Photos: Non members can still view! Jan/06
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Reply to
Mike Romain

Take it to a better tire shop and have them submerge it, then reduce the pressure. If they don't find anything, have them clean the lip of the rim and see if that fixes it.

--scott

Reply to
Scott Dorsey

I'd suspect that your rim has a rough spot on the bead so that when the tire is sitting with the weight resting on just the right place, it develops a leak.

Reply to
Steve

Have someone look over the tire very carefully for a small nail or screw imbedded in the casing. It has probably worn down to where it is all but invisible. They can hold air just fine, but park the wheel at just the right angle and it breaks the seal and down goes the tire.

Reply to
John S.

what he said. My dad had the same issue on his Scout, turned out to be some wood between the rim and the bead from hitting a tree. It looked OK but tire needed to be dismounted and remounted, then all was good. It would only go flat if it was parked with the bad spot down, then the weight would cause it to slowly leak out overnight.

nate

Reply to
N8N

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