m735is

I was under the CR-V yesterday looking for something loose causing the clunk (AGAIN). I went to the back and was pushing and pulling on things. I did find the rear sway bar endlinks are alittle loose, so I will replace those. But I noticed that the rear diff mount moves around (up and down, not side to side) quite a bit. Is this normal?
Also, anyone know what the bar mounted to the drivers side of the diff is for. It's about an inch in diameter, 5 inches long and suspended in a little rubber. This is almost falling out, the rubber on ones side is completely torn and the other side is almost gone. What is this for??

Of course the rear trailing arm bushings are ripping-no surprise there on those typical Honda bushings. I guess 113,000 miles isn't too bad.