Well, in our cars the u-joints are welded to the drive shaft.. you must replace the entire drive shaft. Only other way is to pay an Indie to cut them out and bolt on greasable, open-end u-joints, or have them try to weld new ones on.. both most likely won't work.
Sent from my DROID RAZR MAXX
Koni STR.T, poly RTABs, headers, SSK.
Three Pedals, ZSP.