Tire Pressure

nov/dec motorhome magazine is running an article on tires and inflation. Spend $5 to read or get from a friend. Initial info is for class a's but they are referencing class c tires also. Pretty much as indicated above but may prove to be more benficial to have hard copy information.

Gene in NE wrote:

lanerd wrote:
Tire pressure is all about the "weight" of the vehicle. To get an accurate amount, you must weigh your rv (preferably all four corners..if not, at least by the axle) and then go to the tire manufacture's web site and look at their size/weight pressure charts.

ron

Excellent advice. I have looked at Michelin, Goodyear, and Firestone charts and they are all the same for a given size and pressure. So...you might not have to hunt for a Yokohama pressure chart. ;)

These lists are in the lower pressures to high loadcapacity given.
If you would search the same sise and pressure of Michelin in Europe , you would see that the loadcapacity's are lower.

Best is to use my pressure-loadcapacity-lists wich takes care that the deflection of the tire stays the same over the whole range, wich is the goal of all the calculations. Also those lists are made by calculation.
Can find my lists in next map on my skydrive.
Extra save pressure/loadcapacity-lists
then you have to pic the PDF beginning with the pressure written on sidewall wich is not the maximum pressure of C-load and up.
Then you can pic the list per tire or per axle single or dual, so you dont have to devide by 2 or 4 yourselves.

But also you can use my Motorhometirepressure-calculator to be found in next map.
Motorhome-tire-pressure-calculator
Dowwnload the newest american version ( so tire and not tyre) by RICHT-CLICKING and then open it in Excell or Open Office CALC on your computer.
Dont leftclick or open in web-app wich cant handle some things I used in the spreadsheet and gives notice of that.
In my calculator I use my savest formula and add a reserve first, wich is also advice when looking in the lists.

If you cant work it out, give the details here and I will do it .

Excellent advice here.
Gene's right about different manufacturers' charts all leading to the same result. With all the standardization going on these days that's true. Just be sure that the Size and Load Range are exact matches.
I want to point out that MitchF posted the Truck version of Michelin's chart. They also offer an RV version of the chart. Difference is that the Truck version is "per Axle" and the RV version is "per Corner." They come to the same totals and pressures. Michelin is running on the premise that RVs tend to be loaded unequally side-to-side. So the advice to get Corner Weights is good.
But if you go to the typical CAT Scale at a truck stop, you'll only get Axle weights.
Having your coach weighed, fully loaded and manned as if for an outing, then adjusting pressure accordingly, is a very worthwhile effort.

lanerd wrote:
Tire pressure is all about the "weight" of the vehicle. To get an accurate amount, you must weigh your rv (preferably all four corners..if not, at least by the axle) and then go to the tire manufacture's web site and look at their size/weight pressure charts.

ron

Excellent advice. I have looked at Michelin, Goodyear, and Firestone charts and they are all the same for a given size and pressure. So...you might not have to hunt for a Yokohama pressure chart. ;)

Tire pressure is all about the "weight" of the vehicle. To get an accurate amount, you must weigh your rv (preferably all four corners..if not, at least by the axle) and then go to the tire manufacture's web site and look at their size/weight pressure charts.

ron

Unless you are the original owner, and have not changed the tires to another brand, or size, your sticker on the tire inflation might be wrong. By changing tire brands, sizes, ETC, your tires might now be rated for 80 even 90+ PSI. ALL tires have the PSI recommended pressure on them, you just have to look for it.
I went from LT 245/16 D at 65 PSI to a LT 265/16 E at 80 psi. Thus my OEM sticker is now wrong. So check the tire for proper inflation.
And if you still have the 8 year old tires, better have them checked also.

Thanks much. Great info. We have had this 31' Gulfstream Ultra for about 8 years and don't get out in it as much as we want too.

When you find out what your axle weights are you can use this tire load and inflation chart to determine what tire pressures you should run.

There should be a sticker in the door jam of the vehicle that tells you. With that said, with a 31ft unit I would run 80 in the rear and 75 in the front. That is what my Class C calls for....