I haven't gone wheeling (just got the car a little while ago) and I have no idea if the previous owner did (but probably not, based on the regular all season tires they put on). I have the knowledge and tools, but tools with an asterisk, provided it comes off without too much of a fuss.
As I said, they aren't hard, and they come out if you just grab the axle and and give it a good tug. See bellow
I'm apprehensive because I had to replace a CV axle on my other car and, even though it wasn't terrible rusty, I could not get the axle out of the hub assembly. I had an air hammer, propane torch, three different types of axle pullers, and nothing. I ended up having to cave in and get it done at a shop and it took two days and they destroyed the hub in the process (which they replaced, of course), but man I do not want to go through that again.
Also, another question/concern I had was why the boot tore in the first place. Looking through the service history, that CV axle was replaced about 10k miles ago, but based on the price ($114) I don't think it was with an OEM one. Could it be the aftermarket replacement didn't actually fit right? It definitely looked like it came into contact with the back of the caliper.
If it indeed contacted the caliper, something is wrong. The caliper and the CV stay in the same proximity to each other at all times. It could have contacted the shock I suppose.
Also, would buying a used OEM CV axle be an option? The cars new to me and I plan on keeping it for a while, but I don't feel good about spending close to $400 for an OEM axle right off the bat, especially considering I've already spent a decent amount getting the car up to snuff (brakes, fluids, etc.).
Yes buying used is an option, check the For Sale section here.
Thanks for the reply, I'm learning a bunch about the Xterra, so this is all really helpful to me.
See replies in red above.
Jack up truck
Remove LCA bumpstop
Loosen axle nut (32 mm)
Loosen and remove Tie rod castle nut on spindle
Loosen ABS line from keepers
Loosen brake line holder on spindle
Loosen and remove UCA castle nut. (be sure to have something or someone to hold it for you)
Take rubber faced dead blow mallet and smack the axle nut to loosen the axle from the hub.
Remove axle nut.
Bend spindle outward and forward to be able to push / pull the axle from hub. (be careful not to tug the abs line)
Hold spindle out of the way.
With both hands hold axle straight out from differential, and give it a good solid tug. (should pop right out)
If axle does not come out by pulling, you will need two 16"-ish pry bars get in between the inner CV housing and the seal flange. From opposing sides gently pry until it pops out.
Installation is reverse.
Be careful putting the new axle back in, make sure it is lined up before pushing it back into the diff. If it won't go in by pushing, put the axle nut on the end to fully cover the threads (nut flush with end of axle), and with the same dead blow mallet tap it fully in to the diff.
As for the rust.... plan the day, and spray all nuts to be removed with PB blaster or similar once a day for a few days before hand.
Last trip out we replaced one in a biblical style downpour in 30 minutes. Granted by now I've done this 9 times.
Take some photo's and post them of the current situation.