Just wanted to share my situation... I noticed my exhaust note was louder than normal, for a couple of weeks, and then suddenly the center muffler pipe cracked just short of where the pipe meets the rear muffler.
When this breaks, the front of my rear muffler dropped to the road, dragging along. Not that this is necessarily your problem, but this happened to me...

__________________
Bob Roe
Lehigh Valley PA USA
1973 Olds 88, 1972 MB 280SE, 1978 Datsun 280Z, 1971 Ford T-Bird, 1972 Olds 88, 1983 Nissan Sentra, 1985 Sentra, 1973 230.6, 1990 Acura Integra, 1991 Volvo 940GLE wagon, 1983 300SD, 1984 300SD, 1995 Subaru Legacy L wagon, 2002 Mountaineer, 1991 300TE wagon, 2008 Murano, 2007 R320CDI 4Matic 52K, some Hyundai, 2008 BMW 535xi wagon, all gone... currently
2007 Honda Odyssey Touring, 2014 E350 4matic

I have an old Sears Craftsman "nut splitter" that's worked good for stuff like this. It will literally split the frozen nut on 1 side, making it much easier to get off.

This is exactly what happened to me. It must be the weak link in the exhaust system.

Just had my local indie fit a dealer supplied exhaust to my 300E last week.

So quiet you would not believe, exactly what I wanted, it was expensive with all those fitting kit parts and brackets etc.., but if it lasts anything like the last one, then it's worth every penny.

I asked a few companies about stainless systems, but they want about 50% more than MB, and my mechanic reckons the stainless are noisier than OEM.

Cheers,

Richard

__________________
1989 W124 300E
1991 R129 500SL

That is a cool tool. I tried 3 Sears stores until I found one ($15), but there is no room to get the top of the nut splitter (nut cracker?) over the bolt due to the clamp and muffler pipe being in the way.
A cool tool nonetheless....
It's a real bear to get those bolts off, and the pipes tend to stay stuck onto the rear muffler and front cat. I ended up cutting apart the welds on the old muffler in order to get better leverage to remove the two pipes from the back of my cat.
I used a combination of vise grips, air chisels, grinding wheels, and cut off wheels to get those 4 bolts off. I am told that a torch might help loosen up these very tough bolts. They appear to be copper plated.
All I have left to do is to get a 4" section of the center muffler off the inside of the rear muffler pipe. My air chisel/weld ripper has gotten stuck inside the pipe!@#@# I have gathered new respect for techs...
A call to Phil at Partsshop should get me the few remaining parts I need, 4 nuts and bolts, a new clamp for the rear muffler, and a cat hangar that I noticed had failed. (I want to replace as much hardware as possible.)
I'm tempted to find softer bolts at the local hardware store (easier to cut next time?) but I will stick with OEM just on principle.

__________________
Bob Roe
Lehigh Valley PA USA
1973 Olds 88, 1972 MB 280SE, 1978 Datsun 280Z, 1971 Ford T-Bird, 1972 Olds 88, 1983 Nissan Sentra, 1985 Sentra, 1973 230.6, 1990 Acura Integra, 1991 Volvo 940GLE wagon, 1983 300SD, 1984 300SD, 1995 Subaru Legacy L wagon, 2002 Mountaineer, 1991 300TE wagon, 2008 Murano, 2007 R320CDI 4Matic 52K, some Hyundai, 2008 BMW 535xi wagon, all gone... currently
2007 Honda Odyssey Touring, 2014 E350 4matic