Outer Limits 4x4 Board

Hey transfer flange has been loose for some time now only went looking for the vibration the other day thinking it was a uni or out of balance shaft when i droped it there was some oil in the small cavity between flanges so it worked it was down between the shaft and flange so if anyone has had this happen or knows about it. Main Q is the shaft or flange most likely worn and will keep working loose prob just get a new nut, plenty of lock tight and set rattle gun to phuckin tight and see how it goes.