Had an intermittent front end clunk or rattle in my 2006 350z...single and repeating...during hard cornering or braking, especially on rough pavement, and also when driving normally on concrete. Have a semi-new rack and fresh Bilsteins, car is stock otherwise. Control arm bushings looked fine. Thought something was loose and rocking. Turns out it was the power steering pump bushing. Didn't see this as a potential culprit on various threads and thought I would share.Good luck!