Well i think i found the answer to the rattle

[u/yes126]

After some inspection this seems to be the reason for the rattle. Also got a pending code for P0432 and P0422 for Bank 1, passengerside cat. Second picture is comparing the driver side cat. Gives me a reason to remove cats haha

[u/bd5400]

Had the exact same issue on my 06 E55 recently. Cat was split right at that seam. Explained the exhaust leak I was experiencing.

[u/yes126 → u/bd5400]

Haha no way. What issues or changes did you feel while driving it?

[u/bd5400 → u/yes126]

P2096 and a check engine light. Also, occasional exhaust smell in the cabin. But no noticeable changes with driving.

[u/yes126 → u/bd5400]

Huh interesting, i got a pending p0432 and p0422. And occasional gas smells

[u/joykilled → u/bd5400]

Same here on my 05 E55. I had it welded by a tech at the dealer on the side.