Check this...

Check the center nut on the top of the strut.
Be sure its torque to the correct spec numbers

Mine was loose.... and when the strut compressed, it was moving around in the perch.

The best way to check this is to lift the rear of the car and wiggle the tire and push up to compress the strut.


If it is loose... lower the car and tighten to the proper torque.

I have Ground Control Coil Overs with KYB AGX struts with an Ingots camber correction kit... So I have many noises... But that one was the worst.

It just sounded like something was wrong and it was.

As a precaution, a 4-wheel inspection is part of my routine now that I have done all these suspension mods.
I do a walk around very much like a fighter pilot would just before strapping on his/her jet.

I don't do it everyday but I check it when I check the tire pressures and tread.

Also since the roads are a lot harder on a lowered car then a race track... I carry a deep socket that fits the top nut of the strut just in case it gets loose again due to all the pounded it gets from rough roads.

Good Luck I hope that helps! -Soular