If the boot is torn I would seriously recommend putting in a reconditioned axle. You can reboot it if you want and you will probably find the toughest part is getting the outer joint off of the axled shaft itself. I mount the axle in the vice and spread the circlip that retains the joint on the shaft, with the clip spread I drive the inner race of the joint off with an air hammer and a flat nosed bit. If you do not have access to these kinds of tools you can still do it but I would recommend just changing out the entire axle. I charge 1.5 hours to change an axle out and 2.0 to reboot inner and outer. Parts prices range from around $100.00-$800.00 and you get what you pay for, not that I would give $800.00 for a factory axle but I would not stuff in the cheapest thing I could find either. I am sure that if you look around Bay 13 a bit you will find some kind of tutorial on how to replace it.