Adjust tire pressure for cold weather??

[1Motorhome]

I recently noticed my cold pressure has decreased in all tires (by TPMS) by almost 7 pounds in the mornings with temps in the 40's. But within 10 driving miles they are back to normal pressure.
My question is, should I add more air at cold ambient temps to bring pressure to cold normal settings?

[MN_Traveler]

Oh my. This will be a lively discussion. The "safe" answer is never run them at all, even for a few minutes, if they are below their minimum. This is exactly why i add 10 psi above the charts ... so on cold mornings i dont have to go out and inflate them.

I have no doubt though that other members here will say otherwise.

[Chargerman]

Tire pressures should be set cold and this is why adjustment is usually needed as the seasons change. I wouldn’t adjust if you happen to be traveling to a cooler or warmer area temporarily but if your where you’re going to be then you should adjust pressures based on their cold temperature pressure of the tires

[dfuelman]

Originally Posted by Chargerman

Tire pressures should be set cold and this is why adjustment is usually needed as the seasons change. I wouldn’t adjust if you happen to be traveling to a cooler or warmer area temporarily but if your where you’re going to be then you should adjust pressures based on their cold temperature pressure of the tires

This is the correct method. You will find that the tire will still only climb to the correct pressure, but by starting at the correct pressure you avoid the larger heat cycle. Heat is your enemy.

[MN_Traveler]

Originally Posted by Chargerman

Tire pressures should be set cold and this is why adjustment is usually needed as the seasons change. I wouldn’t adjust if you happen to be traveling to a cooler or warmer area temporarily but if your where you’re going to be then you should adjust pressures based on their cold temperature pressure of the tires

Notsure if i agree with this if you travel from a warm area to a cold area, and your morning tire pressure is below the minimum, if you dont adjust then and there, then you are running on an underinflated tire (at least for a while), and are risking tire damage.

[davidceder]

I put about 7 pounds extra in my tires and never adjust unless things go wrong. I mean if a cold front comes through I would have to find a station to add air. That is a PIA. Then I would need to let air out when the cold front moves through. Repeat, repeat repeat. I do not carry a pump as I don't have the space, want the weight or hassle. I have read on this forum from very reputable involved folks that they fill their tires at the beginning of the camping season and that is it unless they run into some problems. I live at 5000 feet so this AM is was 44 degrees at home and 64 degrees in Phoenix where I am headed. I topped them off at home and that is all. Sometimes I do indeed get an high pressure alert on my TPMS but I just silence it. During really hot seasons in AZ I might up my High Pressure limit on my TPMS so the alarms stop. Just my way of doing things.

You guys that adjust your times all the time, do you do that same thing with your cars?

[Domo]

All tire manufactures state that you should check your tire pressure in the morning before the vehicle has moved more than a mile.

They also will tell you to set the pressure to their chart pressures which they've determined by millions of miles of experience and testing for optimal performance. They also have made sure that their lawyers are happy and that those recommended pressures will keep them out of the courtrooms.

You determine your tire pressure based on weight - which is not part of this discussion (do it the way they suggest on their web sites - or follow any formula you wish to believe in).

The manufacturers understand that temperature increases; during the day, on one side of the rig due to sitting with the sun hitting that side, decreases when it snows or you go to higher/colder altitudes. They also understand that rolling the tires will increase pressures, as will air temperature increase, altitude change and "the phase of the moon." With ALL of those factors considered they made their charts and hope to keep us safe and on the road.

Yes, check your tires each morning before rolling - it's simple (TPMS can make it nearly brainless). Correct, as needed, for where/when you are.

[Domo]

Originally Posted by davidceder

I put about 7 pounds extra in my tires and never adjust unless things go wrong. I mean if a cold front comes through I would have to find a station to add air. That is a PIA. Then I would need to let air out when the cold front moves through. Repeat, repeat repeat. I do not carry a pump as I don't have the space, want the weight or hassle. I have read on this forum from very reputable involved folks that they fill their tires at the beginning of the camping season and that is it unless they run into some problems. I live at 5000 feet so this AM is was 44 degrees at home and 64 degrees in Phoenix where I am headed. I topped them off at home and that is all. Sometimes I do indeed get an high pressure alert on my TPMS but I just silence it. During really hot seasons in AZ I might up my High Pressure limit on my TPMS so the alarms stop. Just my way of doing things.

You guys that adjust your times all the time, do you do that same thing with your cars?

No, you don't adjust your pressure during the day. Overinflation changes the profile of your tires and affects performance - at least according to the Michelin folks I've spoken to on three occasions - but some folks don't seem to believe them.

Here's a good read about tires from a manufacturer;

[RoadTrip2084]

One thing I haven't found is a reference for exactly what temperature the tire manufacturers use for their "cold" tire temp?

If I set my tires cold (before driving for the day) based on the recommended pressures for my weights, that seems like it could be a lot different if it's 32f vs 75f outside. But nobody seems to claim a standard for what "cold" means.

[Domo]

Originally Posted by RoadTrip2084

One thing I haven't found is a reference for exactly what temperature the tire manufacturers use for their "cold" tire temp?

If I set my tires cold (before driving for the day) based on the recommended pressures for my weights, that seems like it could be a lot different if it's 32f vs 75f outside. But nobody seems to claim a standard for what "cold" means.

Ambient is what they want - that's the air as you find it outside in the morning before you roll more than a mile.

"Cold" according to Bridgestone... "Tires are considered cold when the vehicle has been parked for three hours or more, or if the vehicle has been driven less than a mile (1.6 km)"

https://en.wikipedia.org/wiki/Cold_inflation_pressure

[Persistent]

Originally Posted by RoadTrip2084

One thing I haven't found is a reference for exactly what temperature the tire manufacturers use for their "cold" tire temp?

If I set my tires cold (before driving for the day) based on the recommended pressures for my weights, that seems like it could be a lot different if it's 32f vs 75f outside. But nobody seems to claim a standard for what "cold" means.

Setting tire pressure "cold" is not any given temperature. It is what ever the temperature is in the morning before rolling on the tires. Yes it could be 32f. Yes it could be 75f. It is what ever the morning temperature is.

See tire manufactures website for details. Don't try to read between the lines.

[Kenny Loney]

Cold or AMBIENT temperature, that’s when the tire temperature is the same as the air temperature, before gaining any heat buildup from driving. The standard used by virtually all tire manufacturers.
The only time that I had an issue was on a winter trip from home, north of Toronto ON to Florida. I set the tire pressure accordingly to the ambient temperature (minus 30F). MH rode and handled great, until after leaving the campground in southern GA, MH rode very rough and very poor handling. (Before TPMS). Next morning checked tire pressures. What was 70 & 80 at home became 90 & 100 in FL 80F.
If travelling between areas on different temperature, definitely check every morning before driving.
‘COLD’ a relative term, in February at home, when the temperature reaches 32F people get out shorts and a light sweater, counted 10 people in Costco one day in shorts , no jackets. Same 32F in FL, well much heavier clothes.

Ken

[RVStitchy]

To better understand the logic I have a question. Is the difference between cold and hot (ordinary highway running) temps always the same delta? Or will tires come up to the same hot temp regardless of the starting cold temps?

I have lived in South Florida for the last 50 years so not much experience with your frigid sub 40 temps.

I plan on recording this data with TPMS in the future but have no plans to be anywhere this year that is below 50F to experiment.

[Fiesta48]

Way over kill posted here. Check all tires in the spring and fall. And just before each trip. 5 psi difference due to temps won't hurt any tire.
Low pressure will. Doing this for 60+ years.