I dropped my 2011 GT a while back with eibach pro springs but did not change the strut mounts. Of course, it creaked and clunked when making slow turns and braking. I then decided to lower it again with H&R springs and J&M caster/camber plates. The clunking sound is gone, but I am still getting a slight creaking noise when turning my wheel at parking lot speed. I hoped the CC plates would fix the noise, but I guess not. Any idea what may be causing it? Maybe just needs a break-in period?

 

My inclination is that either bushings need to be greased or that something wasn't properly tightened. I haven't done the install myself, so I can only guess.

check these:
http://iihs.net/fsm/?dir=730&viewfil...20Assembly.pdf
http://iihs.net/fsm/?dir=729&viewfil...20Assembly.pdf

is the spring seated all of the way into the pocket of the shock? are there signs of it moving? Did you tighten the strut rod nut and strut mount nuts to spec?

Did you let the control arm dangle during install? It mentions that letting it dangle can damage the bushing; as these are already prone to damage from engine heat it could be the source too.