My rear end clunk is complete gone now. I replaced a rear sway bar and end links with hellwig unit, replaced all of nuts and bolts on lcas and shocks. Also replaced an adjustable panhard bar back to stock. It has been almost 2weeks since and stil no clunk.
It's November now are you still not hearing clunking or rattles.
2011 V6, Race Red, Performance Package, Eibach Sportline Springs, Airaid CAI, Roush Axlebacks, 20x8.5/20x10 Stance VIP Evolution Wheels, Nitto Invo 255x35/20,295x35/20.