Slow Leak
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Pro
Joined: Jun 2007
Posts: 647
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From: Big Canoe Georgia
Slow Leak
I have a 2015 Z51 and my left rear tire has a slow leak that I cannot find. It looses about 1 lb of pressure a week, very consistently. I removed the tire and wheel and looked very closely at the wheel for cracks and the tire for a nail or something similar. Then I put some soapy water around the bead on both sides and also the value stem. I did not see any bubbling. Is the leak that slow that a bubble test would not expose the leak? Anything else? Because there is always a change of a issue remounting tires, I am living with it and adding air every other week.
Racer
Joined: Apr 2020
Posts: 425
Likes: 272
From: Cape Coral,FL
Could be a bad valve stem that's all I can think of since you seem to have ruled out the tire and rim at this point. Take off the vavle cap and throw some soapy water on it see if it bubbles.
Last edited by Punisher44; Feb 24, 2021 at 05:11 PM.
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Burning Brakes
Joined: Aug 2001
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From: Olathe KS
Most likely the valve stem or the bead. You'd have to take the tire off of the wheel to really know if there is a bead problem. I got a new tire from the dealer after a patch when they ripped the bead while mounting the tire on the rim. The tire lost about a pound of air every couple weeks but it was only that tire having the issue. They took the tire off the rim and admitted to ripping the bead, replaced the tire.
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From: Toronto, Canada
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I have a 2015 Z51 and my left rear tire has a slow leak that I cannot find. It looses about 1 lb of pressure a week, very consistently. I removed the tire and wheel and looked very closely at the wheel for cracks and the tire for a nail or something similar. Then I put some soapy water around the bead on both sides and also the value stem. I did not see any bubbling. Is the leak that slow that a bubble test would not expose the leak? Anything else? Because there is always a change of a issue remounting tires, I am living with it and adding air every other week.
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If it loses only a pound a week, that is a pretty slow leak. Could be the bead or the valve stem - try checking them and see what, if anything, shows up.
Race Director
Joined: Mar 2001
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From: Bonneville Salt Flats
Check valve core tightness and run it up to at least the max pressure on the side of the tire before checking. Pressure goes up with hot tires and that is sometime the only time a small lead does so. Still nothing drive it and heat the tire/wheel combo and check for leaks that way. All the best. 
Thread Starter
Pro
Joined: Jun 2007
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From: Big Canoe Georgia
Actually this wheel does not have a cap (lost it at some point). I did previously move a cap to it and it did not help. Also since it did not have a cap I did put soapy water all over it including on top. No bubbles. I still question if a leak that slow would actually bubble enough to be seen.
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
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I had a slow leak that failed the water test. THey dismounted the tire and found the nail by looking INSIDE the tire. It was repaired and the problem was fixed. DIscount tire for the win.
Leaks don't always leak when you want them to!
Elmer
Leaks don't always leak when you want them to!
Elmer
Last edited by eboggs_jkvl; Feb 25, 2021 at 09:31 AM.
Melting Slicks
Joined: Oct 2004
Posts: 2,083
Likes: 710
From: Sunnyvale CA
Sometimes a tire will lose air when parked in one position and not another. I had a slow leak that turned out to be a mold defect in the bead. The easiest thing is to take it to a tire dealer and have them inspect it. Discount Tire / Americas Tire will do that at no cost.
Tech Contributor
Joined: Oct 1999
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From: Charlotte, NC (formerly Endicott, NY)
I agree. I have seen numerous cars have problems with the nut that holds the TPMS sensor in place. There is a torque spec for the nuts but you don't necessarily need a tool to check it. Fingertips work well enough to give it a half turn twist to see if the leak stops. Losing a pound per week is a very slow leak and may not produce bubbles. If you still can't stop the leak purchase a TPMS rebuild kit for that sensor. You will get a new nut and a new O Ring.
Bill
Bill