I have the clunking coming from the RF strut. What am I looking at replacing, the strut or the mount? Through further examination, when putting a socket on the upper strut nut (the one coming through the mounting plate) it will continously turn. The other side will not. Is this caused by a failure in the strut or the mount?

 

It is the mount for sure. If the struts are old, you might want to just replace the mounts and struts on both sides because you need to remove the whole strut to replace the mount.