Just picked up my 2015 LTZ. Could hear the crossbars rattle going down the highway. Mounts are tight to rails and set screws are all the way in but the cross members still rattle. Taking back to dealer for them to fix. If the METAL crossbars would sit in a rubber shoe or something in the METAL mounts i think the rattle would go away but the metal on metal is not a good recipe and really detracts from what is otherwise an awesome ride. Love the truck but this has to get fixed.