[Jerry]

Rod, depending how fast you are making the transistion, you may have to check cold pressure each morning. Heat is pressure. As you reach humanly tolerable temps, it will stabilize. within reason high press is better than low press.

[Archived]

Thanks guys!

We will be in Vero Beach tomorrow. Plenty of time for everything to warm up now!

Where are you staying? We would like to see you again.

[Archived]

If you start out in the cold with your tire pressures set, when you get into the warmer temps the pressures will be higher. The reverse is also true. I add 5 PSI to the pressures Michelin calls for based on my weights and as long as my pressures are at or above my desired pressures I don’t adjust them.

As George or Corey pointed out higher temps will result in higher pressures so I try to check tire pressures before the sun has had a chance to heat up the tires on the sunny side of the coach. The difference between a warm tire and a cold one can be 5 PSI or more.

[Chas]

Hey Rod,

If you had one of these you could push a button to check pressures….

Contct me if your interested…

[jack]

I have that system in mine on bus and trailer it is great , would not be without it!!!!!!!!

[Corey]

Rod & Nancy, We are almost directly west (and a little south) of you. We stay here because that’s where we live. We are between Bradenton and Sarasota. How long are you here ?

[Archived]

Tom, We’re interested.

[Rod]

Tom

We have the Smart Tire system. That was how I watched the pressure rise as I was driving and it was getting warmer outside! Made me a little nervous.

[Chas]

George and Corey-

We are in Vero until the 2nd. Then we move to the Orlando/Apopka airport where we rented hangar space to do a little work.

Keep in touch. Maybe we can meet somewhere?

[Jerry]

Regarding tire pressures when driving.

If the tires start out cold at the pressure recommended based on the weights they carry, it is always going to result in a pressure increase. As the tire rotates and flexes it generates heat. On an 80 degree day it is not unusual for me to measure 135 degrees at the center of the tread and a fairly significant pressure increase. But as soon as the tires cool to ambient the pressures will fall to the proper pressure.

Since measuring pressure after running at highway speeds a few hours is a useless exercise, I use the heat gun mentioned previously to see if all temps are consistent. Even though I start out with different pressures the thing that always amazes me is if I check all the tire pressures fairly quickly they are all usually within 5 degrees of one another. Only when one is out of line do I get concerned. I think stopping and going around the coach to check tire temps is a good way of insuring all is good, plus it is a good way to move a little bit after sitting in one spot for a while.

[Archived]

Jon: Your tire temp procedure is interesting. Of you see imbalance between the corners, duals, or axles … how do you react? Change pressures or change corner weights?

Thanks for all the great information.

Dick

[Robert]

I obviously have little or no control over weights. They are what they are because I can only move the stuff in the coach to a limited extent.

But I weigh all my coaches as soon as I have them loaded with our personal possisions and use that to determine what tire pressures are called for by Michelin. I add 5 PSI to that just because it makes me feel better to have a small margin. When I shoot temperatures they are always consistent from tire to tire. But if one is out of range it becomes a warning to me that something is wrong.

So I will do a pressure check of the other tire(s) on that axle. I make the assumption the tire that has the same temp as the other tires on an axle reflects what the pressure should be. The hotter than normal tire has something wrong and it could be a dragging brake or low pressure. It is worth the time to check as much as possible to find what might be wrong, but if I cannot find anything I inflate it to the same pressure as others on the axle and keep monitoring it often.

I am limited on my air system to 120-125 PSI so I may have to wait for the tire to cool down before I add air.

I had a screw on the inside tire on one trip and I lost about 5 PSI every 3 or 4 hours. I couldn’t see or find the screw because it wasn’t in the tread, but entered at the point where the sidewall and the tread joined so I was able to get home just by adding air every time we stopped. I over inflated it easily because as I recall it never got over 105 PSI when it was hot on the tires on that axle so I just went over that pressure by 5 or 10 PSI.

[Bob]

Jon,

I know you have posted it more than once probably but this might be a good thread to post link to the inflation chart from Michelin.

DKO

[Archived]

Here you go with the load and inflation tables from Michelin. The same information is also now available on the Prevost Car web site.

http://www.michelintruck.com/michelintruck/tires-retreads/load-inflation-tables.jsp

[Archived]

We can put in articles so it’s always easy to find…

Jon?