OK, so I had the dreaded rear suspension clunk, worse on the passenger side than driver's side.  Last December I had both rear lower control arms replaced by te dealership.  Slight improvement, but the clunk was still there going over rough pavement and sharp bumps.
A couple weekends ago I replaced the rear track arms with debluzparts (sp?) adjustable rear track arms.  Clunk is now almost nonexistent on the driver's side, but the passenger side now has more of a metal on metal sound when driving over rough pavement and sharp bumps.  It even makes a slight sound when braking hard and coming to a stop, as if something is sliding back and forth.  I've checked and everything is bolted tight.
Any suggestions on where to look next?  This issue is driving me NUTS! 
