its not my belly pan.
I took it off to make sure.

 

The old strut mount vs the new

 

Hey so I'm guessing you figured out the rod spins when you try to untighten the bolt . So was the nut not on all the way? And man that shock bump mount is rough. I forget what kind of suspension you have? Anyways it seems like your doing everything right, I just hope that was your issue man. If it's not then??? New car? Lol. Oh One thing you should do is try and compress the shock while it's off. If it is hard to push the rod into the shock then it is still good. If it doesn't compress well or doesn't push itself out, then I guess you know a new shock is order. Best luck man. Here's some pics I just took from my Audi A4 bentley service manual. I just took the beginning 1st# and ending pages 3rd#. Maybe it will help?

 

After replacing my strut mount it still did it!
so i held the breaks over a bump and it no longer did it.
Turns out the caliper was loose and was making that noise.


Thanks for all the help MRSnickelSnizer, Chocolatestarfish , and Pbrules.