I have a 96 Toyota 4 runner 4wd. It has a knocking noise in the rear end with acceleration it gets worse. It appears the universal joint at the transfer case is bad. from looking at it there a three universal joints. I'm not sure as to how many I would need. 2 or 3?

 

Most often the complete joint is rebuilt !!

That is one of the things I take to the local Drive line shop.