Cold weather tire pressure

[Roscott]

I'm sure I am overthinking or making way too much of this, but I'm having an issue (mental) with setting my tire pressures now that the weather has turned much colder than normal. I really haven't paid too much attention to this in the past, but now that I have been over inflated (based on recent weighing) and need to bleed down from 110 to 90, I'm not sure if I need to consider the colder weather vs what I set the pressures at while warm. It seems to me that my current cold weather readings of 95 psi are still the equivalent of the warmer 110 psi settings. Then again, psi is psi, regardless of temp. Should I just set my pressures where I need them at time of departure and then check and adjust as needed...regardless of temp?

[PDR John]

95 psi is 95 psi. If that is what you, make sure they are set at that each time before you leave.

[Skip426]

Always check tire pressure before moving the coach in the morning.
95 psi. is what I set at and I find no change in pressure from one day to the next , from 40f, to 75f in three consecutive days of travel.

Or maybe I should say , no change that I can detect at those temps, on my gauge , given my eyesight.

[newmarpusher]

Originally Posted by Roscott

I'm sure I am overthinking or making way too much of this, but I'm having an issue (mental) with setting my tire pressures now that the weather has turned much colder than normal. I really haven't paid too much attention to this in the past, but now that I have been over inflated (based on recent weighing) and need to bleed down from 110 to 90, I'm not sure if I need to consider the colder weather vs what I set the pressures at while warm. It seems to me that my current cold weather readings of 95 psi are still the equivalent of the warmer 110 psi settings. Then again, psi is psi, regardless of temp. Should I just set my pressures where I need them at time of departure and then check and adjust as needed...regardless of temp?

Your cold pressures should always be the same regardless of ambient temp. If you need to be at 95psi in warm weather, you need to be at the same 95psi in the cold weather.

Never bleed down when the tires are warm from driving. Adjust to the proper psi in the morning and leave it there. If the next morning you need to adjust due to different ambient temperatures, do so but again do NOT bleed later in the day from warm tires.

[Arch Hoagland]

In the summer about June when it starts getting hot I set my tire pressure on a day when it is about 85 degrees.

I then don't adjust them until about October and pick a 40 degree day and add air to bring them up to what I keep them set at. I leave them alone until the next summer.

I set them last week in California before we left. Today we are in Florida and saw temps of 27 to 83 degrees along the way. I don't adjust them on a trip and only check to make sure of no loss.

[Bill-MACV21]

I take a slightly different approach with the same end objective as the other posters.

The real bottom line is that we need to roll along at a "preferred" operating psi.

In my case the front ( on a typical summer day) needs to be at 115 psi (cold) with a operational pressure of around 130-135 psi. At altitude or a colder climate my morning pressure might be 105 psi and seem to be a bit low.

However once I'm rolling along my TPMS tells me that I am at 130 psi so I let it go as is. If it started to read in the 125 range I would add more air they evening once the tires cooled off. A reading of 120 would tell me that I screwed up and needed to add more air at the next truck stop (most of them seem to go up to the 130 psi range).

I 100% agree with the never bleed down strategy.

[patch-y]

Camp Freightliner advises check the pressure in the morning(before the coach rolls) and set it to the required pressure as outlined in the tire manufacture weight/pressure charts. Pressure adjustments need to be made for tire pressure variation caused by ambient temp variations. This should typically be done daily. We use a tire pressure monitor system and check the pressure the day before we move (so we have time to adjust for big variation) and check the pressure in the morning before we roll. Weighing the corner weights is also recommended by Camp Feightliner......Freightliner will do it if you get your chassis serviced in Gaffney, and some of the shows, (Tampa super-show) sometimes offer this service.

[newmarpusher]

Originally Posted by Bill-MACV21

I take a slightly different approach with the same end objective as the other posters.

The real bottom line is that we need to roll along at a "preferred" operating psi.

In my case the front ( on a typical summer day) needs to be at 115 psi (cold) with a operational pressure of around 130-135 psi. At altitude or a colder climate my morning pressure might be 105 psi and seem to be a bit low.

However once I'm rolling along my TPMS tells me that I am at 130 psi so I let it go as is. If it started to read in the 125 range I would add more air they evening once the tires cooled off. A reading of 120 would tell me that I screwed up and needed to add more air at the next truck stop (most of them seem to go up to the 130 psi range).

I 100% agree with the never bleed down strategy.

Bill-MACV21,

With a TPMS and the complex understanding of operational pressures that you have, your system is excellent IMHO.

Unfortunately many (most) don't have a TPMS nor a really good understanding of tire pressures, hence my recommendation of checking morning, cold pressures and setting them at the prescribed settings for your weight and leaving them there for that day.

Pressures should be checked each and every morning and adjusted to the same cold pressures each day, regardless of ambient temps.

I have a TPMS and verify my cold pressures each morning before starting off. Like you, I constantly monitor pressures and have a good feeling for what they usually rise to.

As we both agree, one should NEVER bleed air out of a hot tire.

Patch-y is correct. You should get your rig weighed and inflate tires to the tire manufacturer's recommendations for the weight your rig is carrying.

[Tony Lee]

Pressures should be checked each and every morning and adjusted to the same cold pressures each day, regardless of ambient temps.

And in the real world - the one I live in - once a month is more than often enough.

[newmarpusher]

Originally Posted by Tony Lee

And in the real world - the one I live in - once a month is more than often enough.

I respectfully disagree. Checking daily is a bare minimum but you really should have a TPMS so that you ALWAYS know your pressure. Low tire pressure is the main cause of tire blowouts.

["007"]

All good advise and if you have those tire pressure monitors do not panic when you see pressures rising as your traveling down the road, the pressures will change from 10 to 20 psi higher, which they do.
Do not stop and adjust, just check your pressures in the morning when cold for the pressures that you figured out tires should be, after you had your coach weight.

[newmarpusher]

Originally Posted by "007"

All good advise and if you have those tire pressure monitors do not panic when you see pressures rising as your traveling down the road, the pressures will change from 10 to 20 psi higher, which they do.
Do not stop and adjust, just check your pressures in the morning when cold for the pressures that you figured out tires should be, after you had your coach weight.

EXACTLY 007!

That is why I and BillMac stressed to never bleed air out of a hot tire.

[spinn]

Back in my science days all measurements were done at STP- standard temperature and pressure. I believe that you can get temperature compensation tables from the manufacturers if this is of a major concern to you

["007"]

Should have highlighted " DO NOT PANIC" which I am afraid some people might do if they have the tire sensors.