The long yellow arrow at the top of the pic points to a crossmember welded between the exhaust pipes just ahead of the mufflers. It appears to be an adjustable movement damper.

Mine rusted through and broke, causing a loud clatter as the left 2/3rds vibrated against the right. Bending the left side up, so that portion of the crossmember no longer contacts the right, silenced it. However, I still suffer some occasionally heavy vibration, which I described some months ago in this thread:

E350 M272 Engine Vibration

Re-connecting the pipes should stop the heavy vibration. Before going to a welder, is there a clamp-on type of solution?

Attached Thumbnails

 

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2008 E350 4matic / Black/Anthracite

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Gone but not Forgotten:
2001 E430 4matic, 206,xxx miles, Black/Charcoal
1995 E320, 252,xxx miles, Black/Grey
1989 260E, 223,00 miles, Black/Black

I would open a hole in the bracket and smooth out the edges so there is no sharp spots, then buy a stainless steel hose clamp and fish it through the hole and then reconnect and tighten up. Might consider using a piece of bent steel to act as a should for the hose clamp to bear against so that it doesn't get cut.

Does this make sense?

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05 C320 4matic
06 E320 CDI 90k (Totaled by a texting 19 year old girl in a nissan)
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Seems I never got notified of your response.

Yes, what you are saying makes sense.

I have not yet tackled this, however, it would appear the actual source of the vibration is these broken clamps on Photo 1 (one on each pipe); and an easy(?) solution is to use a clamp like the one in Photo 2.


I am guessing those clamps come in different configurations as it seems I would one with the "hook" parallel to the ring.

Attached Thumbnails

   

__________________
2008 E350 4matic / Black/Anthracite

------------------------------------
Gone but not Forgotten:
2001 E430 4matic, 206,xxx miles, Black/Charcoal
1995 E320, 252,xxx miles, Black/Grey
1989 260E, 223,00 miles, Black/Black

Got this all welded today.

The Welder did a nice, streamlined job welding just what appeared to be the vertical rod portion of the clamp in the picture to the exhaust, and hanging them.

Also was able to re-weld the broken crossmember farther back, that I initially thought was the sole source of the problem.

There is a noticeable decrease in vibration, as well as a change in the exhaust note.

__________________
2008 E350 4matic / Black/Anthracite

------------------------------------
Gone but not Forgotten:
2001 E430 4matic, 206,xxx miles, Black/Charcoal
1995 E320, 252,xxx miles, Black/Grey
1989 260E, 223,00 miles, Black/Black