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Run-flat event

Old 02-28-2019, 11:15 AM
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plmmd
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Default Run-flat event

Ok this past monday went to my car after not having used it sunday and my right rear pressure was 24- (Run flat all season) pressured it back up and went to work. Thinking about it all day when parked at work- was down from 32 down to 26 for my ride home- Pressured it back up to 32 awoke tuesday it was 15. Pressured it up to 35 and went to work Now I used it the last 2 days and it stays at 35??????? Looked and see no pathology to explain it though it is a pia to lie on the ground to examine the tread, move the car examine the next seg etc etc.

Also with RF i had no concern about driving to work- If non RF im sure I would have my car sitting at the dealer since monday waiting for tire rack to supply a new tire. (Though as it would be an insurance claim they may have done nothing finding no screw or nail)
Old 02-28-2019, 11:19 AM
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PatternDayTrader
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You cant count on visual inspection. You pretty much have to spray it down with soap water and look for the bubbles.
If you really truly have an intermittent leak, its probably the valve core in the valve stem, and often times, just putting more air in it will make it seal again.

Last edited by PatternDayTrader; 02-28-2019 at 11:21 AM.
Old 02-28-2019, 11:25 AM
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Not sure if this applies in this case, but extreme temperature changes can also affect tire pressure.
Old 02-28-2019, 11:28 AM
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MikeERWNC
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This would be another good reason not to use Tire Rack.

DiscountTireDirect.com would have your tire over-nighted to your nearest Discount Tire Store.
What a great company!

I had a rear Michelin giving a bad harmonic when driving. Not even an emergency and DT had a new tire next day.
Old 02-28-2019, 11:39 AM
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Neil Baker
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Make sure it is not the oring on the valve stem leaking.
Old 02-28-2019, 11:59 AM
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If you have a Grand Sport or Z06, inspect the wheels. Many posts on bent wheels or hairline cracks on the inner side of the wheel.
Old 02-28-2019, 12:04 PM
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plmmd
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thx ill tighten the valve stem - hopefully that's it -

I was hoping to see a nail makes it easier

temp would have affected all four symmetrically
Old 02-28-2019, 12:26 PM
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PatternDayTrader
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Originally Posted by plmmd
thx ill tighten the valve stem - hopefully that's it -

I was hoping to see a nail makes it easier

temp would have affected all four symmetrically
Whip up some soap water and splash it on the valve stem, take the valve cap off, you will know in 60 seconds if that is the problem.
Old 02-28-2019, 12:32 PM
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orca1946
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I have used the soapy solution myself to do a quick check - it works.
Old 02-28-2019, 01:45 PM
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John Harry
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Originally Posted by plmmd
thx ill tighten the valve stem
But not too much - the spec is only 62 in. lb. Over-tightening can make them leak.
Old 02-28-2019, 04:16 PM
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and where does one find a corvette valve stem torque wrench?? Pretty tight sounds good to me
Old 02-28-2019, 04:22 PM
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Foosh
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Any valve stem wrench will work. They are standard schroeder valves.

Ditto on don't muscle it tight. Just twist until you feel a firm stop. If it's loose you'll know immediately.

Last edited by Foosh; 03-01-2019 at 11:57 AM.
Old 02-28-2019, 09:01 PM
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Check that the valve-core is tight. I've seen odd-ball readings if just a bit loose. Every filling can change tautness a little, and the pressure next time.
Old 02-28-2019, 09:45 PM
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Hope the solution is simply to tighten the valve stem. Otherwise, the soapy water routine should show where a leak is.
Old 02-28-2019, 10:56 PM
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c6miller
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It could be a small dark color nail that would be hard to notice and after riding on it those couple of days, it lodge further in the tire sealing the leak.
Old 03-01-2019, 11:58 AM
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^ Yep I've had that happen before. But, it will probably be a continuous small leak, just over a longer period of time.

Last edited by Foosh; 03-01-2019 at 11:59 AM.
Old 03-01-2019, 01:58 PM
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I've had the same thing happen with a cracked wheel. It leaked for a few days and then stopped. It actually developed a second crack and still did not leak. It was very strange. The temperature was the same throughout the whole week this phenomenon happened.

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Old 03-03-2019, 12:07 PM
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plmmd
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took some time and photos under the car while moving it and voila RIM CRACK - bought the tire/wheel coverage so need not worry about warranty
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Old 03-03-2019, 12:25 PM
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Originally Posted by plmmd
took some time and photos under the car while moving it and voila RIM CRACK - bought the tire/wheel coverage so need not worry about warranty
That was my guess as stated in my earlier post on this thread. Way too many GS/Z06 rims developing cracks with no discernible tie to a memorable “event”. Like you, I purchased the tire and wheel warranty. Unfortunately, will either be repaired or replaced with the same problematic OEM rims. Many folks going with forged wheels for peace of mind.

Last edited by runner61627; 03-03-2019 at 12:26 PM.
Old 03-03-2019, 12:53 PM
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boxster99t
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You might also replace the valve stem core on the tire/wheel in question. I had my driver side rear tire leaking (I could hear the air seeping), and tightening it didn't do any good, but replacing the valve stem core did. You can find them at FLAPS--friendly local auto parts store. I believe they were labeled "heavy duty truck" application -- red line ones.

Never mind: saw the post about cracked rim. Doh!

Last edited by boxster99t; 03-03-2019 at 12:53 PM.

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