Hi and welcome to TRS.
There are a bunch of tech articles on this site with loads of invaluable information about these vehicles. If you look up at the top of the page, just under the banner, the third tab from the left is the link to get you there. To help out a bit,
HERE (click me) is a link to a page specific to what you are asking.
Others may still chime in with their experiences. But this gets you some info quickly.
Also, when asking questions, be sure to include info about your Ranger, so that the right info can be given without people having to ask "What year/model/engine/4X4 or 2wd/engine size/transmission, etc.
Many Rangers came with 15" wheels, so that should not be a problem. In most cases, you want the lug pattern to be "5 on 4.5" which means 5 lugs on a 4.5" diameter circle. I think 3.5" backspacing is normal, but 4" will often work well. There will be many tire sizes that will fit. The chart I referred you to will help with that. There is another chart under another
HERE that will give info about engine speed vs mph for various tire sizes.
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