rand4x4

I have a 95 and i had a nasty let go of the gas and thouht something was going to break from tranny to the rearend and would happen 2-3 times in less than a mile.
I Checked the fluids, My transfer case has never been changed and half the level it should be, Changed fluid and then changed our u joints and it was still doing it.
Took it to friends place and did the break and gas thing nothing was loose or worn out. So i was sitting at a light and i could feel the idle rev up and down and it jerked abit. Well my check engine light would come on then be off and i went in and had it checked out. Altanator is going bad, So i replaced that and guess what the clunking has gone away. I mean drive train is tight as hell. Just seeing if anyone has had something like that happen to them.