[1976gmc20]

Well, I don't know what is wrong with yours but I just tend to replace only what is worn out.

But if you're going to do everything then you might as well replace the CV axles because they are hard to get out unless everything is apart. The good part is that the replacement axles that I bought (O'Reillys) had shaved off flat spots on the inner flange so that they easily slipped in between the LCA and the output flange. I finally got the (original?) ones out using a six foot pry bar, but if I had known the trouble it would be I would have borrowed a torch and just cut the axles in half to get them out.

And … if you're that deep then you might want replace the sealed bearing hubs while everything is apart.