Came to this topic , searching with google for tire-pressure-calculator.
Dont have a jeep, so wont introduce myself in a seperate topic.
In 2007 I got hold of the formula, the European tyre-makers use , to determine the advice-pressures for radial tires for cars, and worked it out.
Learned myself Excell to make spreadsheets for it.
After I declared this formula holy, I translated a few from Dutch to English to go worldwide with this official formula.
Found out by reactions , that this formula was not that holy as I thougt, and found an article of an American, with a new one , and comparison with the old one. Also found out that in America a wrong formula was used before 2006 and still is wrong for C-load and up.
Constructed my own formula, wich is a combination of the old and new.
So I made my own calculator, wich could lead to verry low pressures for Jeeps with their oversised tires. Already read something about the Jeep-desease ( walking kidneys).
This link leads to my public map of skydrive with 2nd from bottom a spreadsheet wich can be used best for this site, and where you also can play with the temperature , to see what it does to the pressure. It workes still with the European formula.
But there is much more.
To use a spreadsheet , click on the line , but not on the name of it, then in the right barr info. Click there on download. After Downloading, and eventual viruscheck, open it in Excell or compatible to use it.
If you press wrong, it will be opened in the browser, but it gives notice that it cant handle it because of things I used in the spreadsheets.
Then press skydrive at the top to go back and try again.
This calculator is better then the miles gallon one, because it uses the offially used formula.
In the map "all about tire-pressure" expirimental spreadsheets, also myownformula 2nd from bottom , wich can be used in the browser, and explains my universal formula and where you can make your own list , like the tire-makers give with different formula's.
You can navigate my map like in a forum.
Succes and ask me if you want to know more
Greatings fromm Holland