That's not 'normal', altho it's also 'not unlikely'!
Do you still have the OE sway bar, or more likely, the OE sway bar links &/or bushes?? :dontknow:
The 'heim joints' on the ends of those OE Sway Bar Links are prone to seizing, or at least becoming quite hard to move, and that can cause a clunk like the noise you describe! The main Sway bar/frame bushes can also wear, and so they could well be the culprit too; or the OE Links themselves have been known to warp & twist, making noises like those you describe; while the 'placcy' links themselves can even even fail & snap/break in halves, so that when you do the bouncing exercise you describe, you get that lurch/clunk..... or you can get a combination of
all of that lot, where the seized heim joints force the frame bushes to flog out, flexing & twisting the cheap placcy OE Links until they break, but then due to seized heim joints, the links still sit in basically their operational position and as the sway bar flaps around during any bouncing/suspension movement, the ends of the snapped links hit each other & make a noise & lurch as they forcefully move past each other! :gaah: Do you really need to ask me how I know all this, particularly that last one!

So, if you still have the OE Sway bar, there's a LOT of things that it could be!! :banghead: The solution to all of this lot is to replace the sway bar & links with an a/mkt unit that's made out of better quality materials - something like BajaRon's Bar & Links!

hyea:
However, having had a BajaRon Sway bar fitted for some time might not
necessarily exclude
it from causing that sorta noise too - there've been
some, albeit
VERY FEW, instances of the heim joints on Ron's original style 'dog bone links' seizing or
almost seizing, so that as you bounce they 'clunk' as the almost locked heims are
forced to release aggressively - this is why Ron developed the newer style links with better heims; and if you think it might be your old style 'dog bone' links from BajaRon causing this noise, then you should call him immediately & discuss your options. :thumbup:
Of course, this is only one set of possible 'clunk causing' issues, there are probably quite a few others too. But if I was gonna bet on it, I'd be backing the OE Sway bar &/or Links/heims over the rest!

Over to you! :cheers: