PDA

View Full Version : Tire pressure question


Maineiacs
10-26-2021, 11:23 AM
Recently finished a trip of 400 miles with no issues, no fluctuations in TP. Getting ready to head out again and one tire dropped from 80 to 55 almost overnight - while sitting in the driveway!. (3 or 4 days ago, pressure was fine) I did reposition the rig earlier today which involved several sharp turns. I'm 99% sure there's no leak as such - but is it possible that with a sharp turn the sidewall flexes enough to let air escape?


If it's still holding pressure in the morning, we'll hit the road. If it's dropped, we'll stop and have it tested in a dunk tank.

German Shepherd Guy
10-26-2021, 11:44 AM
I am putting my money on a small hole. Probably filled with a screw. But, that said, my money would amount to only a 50 cent bet. Please let us know what you find in the morning.
Does not seem likely that a sharp turn flexed sidewall enough to let air escape. How would it reseal?
Where is CW the man when you need him?
Oak

jsb5717
10-26-2021, 12:10 PM
Personally, I would have it tested before I hit the road. Losing 25psi overnight isn't normal. My money is also on a screw, or nail, or, whatever.

flybouy
10-26-2021, 12:30 PM
I had a tire valve that did stupid things. Would take 3 weeks to leak 10 lbs then turn around and it would leak down 10 psi in 2 days. Put on the spare,npumpednit up and paid a visit to a tire shop near where we were camping. Tire tech used a 1/2 bottle of soapy solution and could not find a leak. When we got home I went to the tire shop I go to and the tech found the stem leaking in <1 min after placing it in the dunk tank. Moral of the story is you have a leak. Find a shop with a tank and you will find where it's leaking.

sourdough
10-26-2021, 12:31 PM
I'm with the test it before travel club. An object in the tire can stay there and hold pressure for a while or come out and let go. A sudden loss of pressure in the tire can lead to a series of failures. Better safe than sorry.

CWtheMan
10-26-2021, 03:27 PM
Before you can trust that tire again you'll have to insure it, the valve stem and wheel are not leaking. I doubt very seriously that a tire will roll of the rim a bit in a sharp turn. It would almost surely be some sort of defect. However, they have been known to pass air when hitting a chuck hole or sharp curb.

Maineiacs
10-26-2021, 03:40 PM
I suspect all of you are right. Guess the first order of business tomorrow is to pull the tire off. I'll post an update after.

Ken / Claudia
10-27-2021, 06:13 AM
I would have pulled the tire off and rolled it, looking at all parts for defects. Put the spare on and took the one losing air to a shop if I found the problem or not. It's just not worth the possible problems or damage if the tire is not 100%.
At 65 I can still take them on/off. Heck whos going to do switch out tires on the road out in no where. Maybe it's the valve, or a screw who knows till you look.

Maineiacs
10-28-2021, 11:50 AM
At 65 I can still take them on/off. .


At 75, I can also change my own.


The tire was at a cold 75 when we checked in the AM. There are exits and malls at virtually every exit for the first 30 miles or so, so we rolled out. It's been two days and almost 500 miles and no issues. Pressure gets ups to 87-88 after it warms up, which is the normal range for all 4. At this point I'm suspecting the schrader valve rather than the tire.


When we return the tire will be pulled off and examined closely and the valve will be replaced with new. I appreciate all the opinions and advice offered.

Ken / Claudia
10-28-2021, 12:46 PM
Agree sounds like the valve.

JRTJH
10-28-2021, 03:26 PM
I just had a valve stem replaced on a truck tire this afternoon. For the past 3 or 4 months, the tire has lost a couple pounds of pressure in a week, then might go 2 weeks without losing any air, then lose 3 or 4 pounds again "seemingly overnight". I check my tires ever Monday Morning, so I've been watching this tire closely. Today we were in town, the WalMart auto service didn't have any cars in the bays, so it was a perfect time to let them take a look. The valve stem was leaking around the rubber where it seals against the wheel. So, it can happen on trailer tires and also on truck tires.....

flybouy
10-28-2021, 03:32 PM
At 75, I can also change my own.


The tire was at a cold 75 when we checked in the AM. There are exits and malls at virtually every exit for the first 30 miles or so, so we rolled out. It's been two days and almost 500 miles and no issues. Pressure gets ups to 87-88 after it warms up, which is the normal range for all 4. At this point I'm suspecting the schrader valve rather than the tire.


When we return the tire will be pulled off and examined closely and the valve will be replaced with new. I appreciate all the opinions and advice offered.

One thing's certain, mechanical things don't "heal" or fix themselves. It leaked for a reason. Safe travels.

Tireman9
10-31-2021, 07:25 AM
At 75, I can also change my own.

The tire was at a cold 75 when we checked in the AM. There are exits and malls at virtually every exit for the first 30 miles or so, so we rolled out. It's been two days and almost 500 miles and no issues. Pressure gets ups to 87-88 after it warms up, which is the normal range for all 4. At this point I'm suspecting the schrader valve rather than the tire.

When we return the tire will be pulled off and examined closely and the valve will be replaced with new. I appreciate all the opinions and advice offered.


Yes one significant benefit of TPMS is that it eliminates the small but not zero possibility of having a valve core not seat properly and leaking. The OP did not say how he learned about the air leak so we can only offer guesses on his air loss but in my experience leaking at the tire/wheel interface due to hard cornering is an even lower possibility than having a valve core leak.

goodellj
10-31-2021, 08:43 AM
I once had a loose valve stem, but my money is on a nail or broken belt. Losing 20+ pounds in 2 days needs to be explained. Thoroughly check the tire with bright lights and look for a nail or screw, or any kind of bulge or bald patch. If you find no problems, then take it to a tire shop. I have done this and found nothing, and then went to a tire shop and the tech found a screw within 20 seconds. Those guys have "educated eyes"