This weather is a real pain on tire pressure, I try and keep my Firestone Wide oval's at about 34 (when at operating temp) but with this big range of temps outside its a real pain. If I don't drive the car for a few days then start her up in the cold mornings, like today, I get low pressure warings, saying that a few wheels are at or below 24, but when they get warm the pressure goes up to about 27 to 29.
I guess what I am going to have to do is air them up to about 32 on a cold moring and see how much it will go up when they get warm. These cold morning and warm afternoons are a real pain , at least we are not having to deal with Sandy.
Hope all of you East Coast guys are doing OK.

 

Thats the benefit of using Nitrogen. Its more stable. I use to think it was a gimmick but its not. I don't have it in my tires but if I get a chance I will get it put in. Some tire stores have a one time charge for it for life of the tire etc. I can see the benefit in these low profile tires especially.

 

Rough rule of thumb is 1 psi for every 10 degree F change in ambient temp. I set mine at 30 psi on a cold morning in the garage (50F) and they are fine. I have the same issue every year when fall rolls in.

 

I agree, ambient temperature changes can wreck havoc with maintaining proper tire pressures. If your tires are 24 lbs cold and you're seeing low pressure warnings you've got some adjusting to do. I wouldn't over-inflate the tires when it's the coldest but I guess you just need to play with it until you achieve the pressure range you want....find the happy medium.

I know guys at the track who use nitrogen but for a street car I'd only use nitrogen if it's free and convenient. Nitrogen is somewhat more stable with respect to temperature related pressure changes but it still leaks (albeit 1/3 less than air) and many suppliers don't provide the level of nitrogen purity required to be beneficial...the nitrogen fills are corrupted. Use nitrogen if it's free and convenient. I don't consider having to go to a dealership or service facility just to fill my tires convenient. If you're going to use nitrogen buy your own tank so you can do it at home (or at the track). Otherwise, I think you're just as well off using dry air.

PS What drives me crazy is checking and adjusting tire pressures at the track when one side of the car is sitting in the sun and the other side is in the shade. Couple that with rapidly cooling hot tires and it's a challenge to get the tires precisely where you want.

 

besides the "1 lb. variance per 10 degrees, either direction" if you're running at 27, your cold inflation pressure is much too low to begin with. I think your 32 hot while running is also too low, but that's your judgment call. must be a reason why GM calls for minimum of 30 cold, for/on the street.

just remember that most tire engineers would rather see a street tire slightly (stress: slightly, not wildly) overinflated, than even a couple pounds underinflated.

 

What would you guys recommend in the cold/warm for the stock tires?

Also, is the displayed pressure in the car accurate, and how often does it update?

 

You need to lose your concern for the hot operating pressure. The proper way to measure is to set them in the morning when they are cold. If you want to add or subtract from that, it's up to you...but cold is the pressure to worry about...forget the hot.

 

In the winter on my Z06 I set the cold pressure at 32(so I end up with 34 when warm), and in the summer I set the pressure at 30(so I end up with 34 when warm).

I do the same for my DD but to different presssures as the DD calls for different pressures when cold(28 front and 32 rear).

You loose about 1 psi for each 10 degree drop in ambient temp.

 

The purpose of the DIC pressure display is to let you know about a puncture...for inflation, use a good handheld gauge. 30 psi cold is what is recommended for the stock tires. Cold is considered to be first thing in the morning before driving the car.

 

good advice from above two respondents.

 

I always try to set mine at 30--31 psi cold, all-around. When the ambient temperature changes, I adjust the cold tire pressures as required...

 

Exactly, always check and adjust air pressure when cold.

 

Thanks for the good advice seems like I need to set my cold pressure up some, I have always set it doing the day but now going to check and set it in the mornings when the temp is down. Thanks

 

Yes, get your cold temps correct and adjust seasonably from there.

I have Nitrogen for free in one of the non-Corvettes and I have not found it to be much better than air. For ambient temperature changes, it will change just like air (which is 78% nitrogen already). It does lose slightly less over time, and change slightly less as the tire heats up, as well as hold less moisture which in theory is good for the tires, so there are some benefits, but I wouldn't go out of my way to use it. There's nothing magic about it and you still need to adjust pressures for the seasons.

 

I had a similar situation recently, got the, " Right rear tire Low" prompt on the DIC in the mornings at first start up, after a few miles the DIC went back to normal......this happened everyday for a week until I finally stopped and filled my tire pressure to cold PSI 38- the tire pressure was in fact low according to the gauge on the Air station I used. A few days later I got the " Right rear tire pressure is high!" This happened when I did considerably more driving than usual, after arriving home I did in fact check my tire pressure when warm and registered over 42 PSI, I than let out some air and brought my PSI back to 36 and have been fine since, I wasn't aware that the Tire PSI system monitors both high and lows, I won't rely on the filling stations gauge from now on, I have my own in the car which I will use from now on,

 

yup

 

I went to weather.com and printed out the average low temperature for each month in my town, tacked it on the wall of my garage.

Once per month I adjust the pressures to give 30 psi at the average low for my town.

Example:
The average low in November for my town is 27'F. I go out to the garage one morning in November and the thermometer inside says 47'F, so that's what the tires are at. To account for being 20' above the normal low, I set the tires at 32 psi. I only do this once per month, and just ignore the day to day fluctuations.

The tires normally increase 2-3 psi from the heat of flexing while driving, but that sometimes is compensated by the outside air being cooler than my garage.

My TPMS is with 1 psi of my various digital gauges (which all read the same), but people who live at higher elevations report greater differences.

 

36 and 38 PSI is WAY too high. You are losing traction and handling by running that high of a tire pressure. Just like the sticker on the door jamb says; 30#'s Cold is correct. Read "cold" to mean ambient temperature.

 

And use a regular tire gauge if you are out west. I can tell you that my TPMS in Utah for my cars is about 10% off. For a Corvette a real cold morning can set off the warning light.

I have noticed non run flat tires seem to go up less when warmed compared to run flats.

 

what I do is aim to set the pressure at 30 when they are cold outside of my garage - the pressure can fluctuate from there all I care