Not sure if what I have is the same as others. When I go over a bump at slow speed I get a "noise". Not sure I'd identify as a clunk. I jumped on back of truck and can hear it a little. HOWEVER... if I shake the truck side to side by grabbing the bed rail I hear it. From what I can tell it looks like the leafs are sliding side to side. On my Jeep (Wrangler YJ) the leafs have clips of sorts to keep the leafs stable.
Thoughts? Is it the same issue other are having?