Today, I noticed my rear tire of the Chevelle was low. The car has been parked for atleast 5 days. I figured I must of picked up a nail some time last week. A little later on, we were heading out to the store and I glanced at that back tire again and it seemed lower already. On the way home from the store, I stopped at the corner gas station to make sure they had the air hose out, I figured I could fill up the tire and the tank at the same time. I got home, grabbed the keys, but the tire was now completely flat! How does that happen? When I got home from work the tire was low, but certainly able to be driven on and less than 6 hours later it was flat.

Short of someone letting air out of the tire a little at a time, I'm stumped.

The tire had a leak. The leak got worse. It happens.

I exploded a tire on my truck; it was a "little low" when I left home; and 20 miles later I'm on the shoulder of the road putting the spare on.

I had a similar problem once but mine was only flat on the bottom.
l:)
(Sorry...couldn't resist!)

Um ... I think you have a slow leak in your tire. Nothing weird about it. You oughta get that fixed.

Um...I realize I have a problem in the tire.
I was a little hesitant about this post thinking I would sound a little bit "slow"......
"uh......uh.....My tire is flat....duh.....how can that be....duh...."
Maybe I didn't explain it clearly enough.

No flat yesterday morning...I go to work, the Chevelle stays home in the driveway where its been for almost a week.
I get back from work...using another car, remember, the Chevelle stayed in the driveway
Chevelle tire is low(The car hasn't moved in about 5 days)
Going to store a few hours later in another car...(The Chevelle still hasn't moved). I noticed that the tire was lower.
When I get back from store, still using the other car, (the Chevelle hasn't moved) the Chevelle tire is now flat.
How does a leak develop while a car is sitting still? And go flat in a matter of hours?
If I picked up a nail last week, there would have been a gradual loss of air, or a sudden loss of air. The rate at which air escapes a hole in a tire is probably somewhat consistent. If I drove on the low tire, now that would have been explianation enough. The strange thing to me is that the car hadn't moved in days and the tire went flat rather suddenly.

Reseat the valve stem and air the tire back up. See if it still leaks. If so look for any nails, etc. in the tire. If no nails, then go around the tire with a squirt bottle of water or slow trickling hose and look for air bubbles. Check for bubbles at the valve, the bead (where the tire meets the rim) and in the tread. Where you find the bubbles is where the leak is coming from. Mark the leak and take it to the tire shop to get fixed. Tire shops like it when you find the leak for them. Makes thier job easier.

I also noticed by the picture in your signature your chevelle has metal rally wheels. Make sure you don't have any rust forming on the wheel in the bead area. That will also cause a slow leak.

Assuming it's not the valve - by driving it more, you likely drove the nail/screw into the tire further and increased the leak.

There could also be a loose screw right behind the wheel.:yes:

I have one on my Chevelle that does the same thing. When i drive the car it would stay up but when parked it would go flat after sitting for a while. I'm thinking its the bead but i don't know.

The timing sounds like a coincidence. Take some dish soap and water in a squirt bottle and soak the tire to check for bubbles escaping.

The air escaped :D :D :D

Tire leaks, tire flexes, leak gets faster, tire flexes, leaks gets faster, tire flexes lea .............................

I also noticed by the picture in your signature your chevelle has metal rally wheels. Make sure you don't have any rust forming on the wheel in the bead area. That will also cause a slow leak.


I agree with 350. You live in NY. They put salt on the roads in the winter. Rust will do that to your wheels. The solution is to clean up the wheel/tire mating surfaces properly.

I had something similar just last week.Ever since gas took a flying leap I have been very carefull with the tire pressure. I noticed I had one tire that over a week would lose a half a pound of air and over two weeks not quite a pound.No big thing right.So I'm off to the auto parts store and as I stop for gas,I notice the tire seems a little low so I go home instead.I look the tire over spray soapy water all over it including the valve stem,I find one tiny little nail,that almost no bubbles came up so I easily could have missed it.I figure thats not that big a deal and its to late to take it to the tire place so I hook up the air hose and go start the compressor,and only the weight of the hose pulling down on the valve stem showed up as the leak.I could hear the air leaking,but as soon as I unplugged the hose it stopped.I had to bend the valve stem over pretty far to actually hear it leak but soapy water still didnt show a leak if the pressure was low. I would check the valve stem.

It could be the position of the leak. As the tire looses air the leak area could become more exposed allowing the air to escape faster.

Or your wife, friends or neighbors are just screwing with you everytime they see you drive off :D

I have had the same deal. The tire will hold air for months, then leak down in a couple days. And then hold air for weeks. It seems that there may be a nail in it that is affected by the nearness to the ground. If the tire is rotated so that the tread is flexed just right it will leak, otherwise it stays air tight.

Consider this: if your stem or bead or rim were the culprit, when you parked it the SECOND time, the tire was rotated to a different position that made the leak worse.

I appreciate all the help/thoughts guys. Thanks it turned out to be the bead. As the pressure lowered there was less force holding the tire to the rim. Once it dropped to a certain pressure the air came out almost instantly.