This is a good source for things to look for >>> https://comancheclub.com/topic/57071-mysterious-clunk-please-help/?tab=comments#comment-585215
Quoted from one of the replies to that link:
"Worn bushings in control arms..........those will clunk, again, if those have been inspected.......set aside.
Steering link will clunk, tie rod ends..........if you are assured that is not the problem...............set aside.
Gear box to frame, frame can crack, steering box lose.............inspect, tighten.
Lastly, and here is where I think your problem is-
Track bar- If hole is wallowed at axle end..........clunk.
If fours bolts are lose at frame end..........clunk.
If rod end at frame bracket is bad.......clunk.
If hole on frame bracket where TB rod end is mounted had wallowed.........clunk.