Intermittently, when I make a turn to the right, and hit a bump at the same time (such as pulling into driveway) there is a loud clunk coming from the drivers side.  It sounds like some linkage near the wheel or the rack and pinon.  I took it to my mechanic, and of course it wouldn’t clunk for him. but he did tell me that there was about a half inch of play in the racks passenger side, told me it should be replaced soon, but the part was $800.  He said that the play would give a little shimmy on the highway which I confirmed. He tightened the bolts on the rack, and off I went. Miraculously, no clunk for a week. But then it came back. So I tightened the rack bolts again (cranked!)but still there, and worse.  So I went to the junkyard and got a semi used rack with arms for $150, and installed it myself with new bushings, and had the guys at the alignment shop (would need it after new rack) put the air ratchet to the rack’s bolts when I took it in. Things were good for a couple weeks, plus no more highway shimmy.  Now it is back again.  So do these rack bolts (which are never loose, just not super torqued) need a re-torque-ing with loctite?  Or is something else moving? such as the way bar? Nothing appears to be loose, and I replaced the shocks when I did the rack.
 Any and all ideas considered at this point.