I can't remember if UPR was one of the brands or not, but I have read in some posts on the board that some C/C plates are making a clunking noise once installed and driven. Might want to do a search on the board, (I would help you out, but I am being VERY lazy right now.). Try adding the Steeda plates to the search because I am SURE they were one of the brands mentioned. As far as for your noise, you may want to joust your suspension while you are under the hood and see if that will help you out with finding the source of the sound. If it is determined to be the C/C plates, I would call UPR and make sure they were installed correctly and then either get a refund or exchange set up. Most importantly, any bolt you loosened for the install or for the alignment setup, just take another look at it and maybe retorque it to ensure everything is secure.