77 done much work on my own.this one stumps me.replaced half shaft u joints.I know there correct.when I really put the heat to her I get a thumping on only the right rear.as soon as I let off throttle and I'm still rolling it stops.any ideas?

 

Welcome to the forum.

Did this start right after the U-joint replacement? First thing that comes to mind is wheel bearing.

 

Yes.wouldn't it b all the time not just when I'm in the throttle if wheel bearing?

 

Not necessarily. You didn't lose any of the needle bearings when installing the new U-joints?

 

Had a machine(race) shop replace them then I put them back in.would it only thump when there is touted on the shaft?

 

Not sure what "touted" is.

But if the shop wasn't familiar w/ the correct procedure for installing, they may have messed it up.

 

Sorry that should have read Tourqe.dam computer won't let me say that.don't know this was a high performance speed shop.friend told me today could b cap misalignment.have not taken the time to look.Thanks for your time

 

Hope you find the problem. Let us know what you learn.

 

Still got trouble took it all apart.put it back together still thumps.maybe it its wheel bearings.do they just go?no issues before.

 

Try swapping the two rear tires and see if it stays the same or goes w/ the tire.