When replacing a wheel bearing I mucked up the threads on the axle (half shaft). I'm talking about the threaded end that accepts the hub nut after it is pushed thru the hub. I want to repair the threads with a die (they are not that
bad).

What is the size of the threads on the end of the axle?

I'm guessing M22 x 2.5mm, looking for confirmation.
Anybody?

Try tap in nut to determine appropriate die to use, is my first suggestion. Alternately use the portion of the other side's exposed shaft to try and determine die size. Manuals do not give that detail info. Might be listed with hub nut part # at dealer.

If it's not that bad, maybe you can just screw the nut back on and let the thread in the nut cut the correct thread back on. Don't try to screw all the way tight until you know it's okay (ie, don't make it worse). I just changed my bearing this weekend and had to do the same on the lower ball joint bolt. Grant it, my mistake would is a lot cheaper if it hadn't worked!

I'm looking for this info here at work--so I can order a die from McMaster-Carr. I tried to gently thread on the old nut to "cut" new threads, as well as using a thread file. It still will not engage the nut! I will just wait till I'm home and take the nut to a hardware store.