So I have my car in the garage and I have noticed that the tires are getting low with the cold weather. Their also low profile so I'm getting nervous that I may mess them up if I don't keep an eye on them and fill them up periodically. Should I jack the car up and put it on jack stands over the winter. I've heard that is one method for storing.

Any idea or suggestions from folks that live in the cold Midwest.

 

Look at the sidewall and fill to what ever the max air pressure is listed.

 

My biggest concern is that tires will get cracks on the sidewalls from being permanently flexed (as in flat). If you don't routinely monitor the pressure and fill as needed then taking the weight off them with stands would be a good thing. Support the suspension such that the weight of the car is on the springs, however, to avoid stressing the rubber suspension bushings.

 

Yeah I just really noticed it the the other day as i was pulling in, turned on the compressor and filled it up but I know i got a good 4 more months of cold. I'll see if I can jack it up slightly and get some stands under it. Paid too damn much for tires and only had 4 months on them.

 

Let's step back for a minute here and do a little high school chemistry.

From the ideal gas law, the pressure in the tire should vary with the ratio of the absolute temperatures. Let's say that you fill the tire to 35 psi when the temperature is 70 F. That's equal to 294 K. If the temperature were to drop to 0 F, which is 255 K, and it's probably not THAT cold in your garage, the pressure should drop to 255/294 = 0.87, or 87% of 35. That's a little over 30 psi.

My point is that a change in the tire's pressure from a normal fill level at room temperature to what it would be on a cold winter day should not be noticeable by visible inspection.

Your tire's pressure would have to drop to typically 15 to 20 psi before you would be able see that it looks soft. If you are seeing what looks like a soft tire, I think you should consider the possibility that you have a leak. Especially if you find that you have to pump it up every week or two.

 

@Jaunty75 I thought the same but what made me negate the leak scenario. Is that its happening on random tires. All 4 tires were fine all summer even when I put the car up but recently with the Chicago temp hitting like 21 degrees I'm seeing different tires deflate. First it was front pass, now its driver rear. So I'm gonna top them all off this week and monitor them. My garage is attached to the house but its pretty damn cold in there.

 

If you're seeing multiple tires deflate to the point that the loss of air is visible, and the temperature has dropped to only the low 20s, which should cause a drop of only a few psi from the pressure at room temperature, you may have tire fitment issues. Perhaps the colder weather is causing the tires to pull back from the rims? I've never heard of such a thing, but something is going on here to cause your tires to lose pressure that is due to more than just the drop in temperature.

 

Will keep you posted I'll be checking and topping off all four tonight and will seriously monitor from there.

 

Has anyone ever tried this or anything like it? This one was written up in the 1/7/16 issue of Old Cars Weekly.

http://www.flatjack.com/







They're not cheap. $120 each for tires up to 195 mm width and $150 each for widths up to 345 mm.

 

A different approach that has been suggested a few times is to have some junk wheels and tires on the car with the good ones stored somewhere dark and dry.
If you need to move your car in a hurry, like fire or flood, you can, and if a tire goes soft it's nothing to sweat over.

Roger.

 

FWIW, I live in a pretty harsh climate here in Centennial, Wyoming.(8350') I park my 1968 Cutlass 'S' in my unheated pole barn all winter(6 months or so) and the tire pressure reacts just like Jaunty75 says you should expect the pressure to react. I pull it out in May or June check the tire pressure among other things and usually have one tire that is a little low on air. I fill it up and don't have any trouble the rest of the summer. I have to agree with Jaunty75 something is going on more than cold weather. But then again I'm a rookie!

 

This is fine for the problem of tires developing flat spots when the car is in prolonged storage. But it does not address the problem the OP is having. His tires are losing pressure, and that'll happen whether they're on the car or not.

 

It's that wonderful ideal gas law!