Muffler Replacement on W124 - questions
 

I am replacing the rear muffler on my 1990 300E with an OEM muffler from the dealer. I am going with oem because I like to keep the car quiet. The cost ($297) is actually cheaper than aftermarket ones like walker.

I am going to go to a muffler shop and get them to put it on.

1) Should they just cut off the rear one and clamp the new one on? Are there any issues if they weld it? Wouldn't that be better, so no chance of leaks? Because I read on some other posts that the exhaust should never be welded and I dont understand why not?

2) I want to add 2 chrome tips. So some custom work would be required once I find some tips that will work. Any issues here I should be concerned about?

3) Do I need to buy a new clamp and the 2 rubber rings from MB? Can I just re-use the old ones? Would the muffler shop have these for my car, or do should I have them beforehand (if I do have to install new ones).

thanks guys.

I would replace the clamp and rubber hangers with new ones. You're in there paying labour anyway. Why risk a headache if one of those inexpensive parts fails.

Do you think a muffler shop have the clamp and rubber hangers or should I get it from MB?

The OEM setup most likely has the tips angled downward. I am assuming the tips you desire will be perfectly horizontal. You might run into a clearance issue with the rear bumper.

1990 w124 Muffler Relpacement
 

Several months ago I replaced the center and rear mufflers on my 92 300E w124. I bought OEM units from a website out of Dallas. The mufflers were shipped from CA. I bought the rubber hangers and metallic type gaskets from the same source. I toke my car to a local Meinike shop for installation. They welded the unit on because I didn't want to take the chance of a leak. My total $$ for mufflers and installation was $387.xx. My advice is buy new hangers and metal gasket where the middle and rear connect. The pipes on the rear muffler turn down because this an OEM muffler.

Tarheel75 :)

Depending on the welding conditions, some stainless exhausts can become sensitized after welding. A sensitized weld is susceptible to brittle cracking in corrosive environments. One of the auto companies paid me good money to study this phenomenon on some warranty returns.

If the weld is done on clean surfaces with little carbon pickup, and is not held at certain temperatures (around 900°F) for too long, then it should be okay.

If you cut off the factory turn downs and run straight out, you will hit the bottom of the bumper.

Either drop the muffler slightly, or cut out the bumper.

Jim

Disregard whoever told you not to weld it back together properly

I had to replace the exhaust on my 300SEL from the cats to the rear. Picked up the new parts, Eberspaecher, had them installed and welded the resonator to the muffler.

If Kestas speaks,It is so.
 

Kestas will not bother to speculate.
AND He only Addresses matters that he has personal experience in.
(So,go ahead, ask him if he's a Forensic Metallurgist)

I didn't discount his post, I was talking to the original guy.

Cheap u-bolt clamps are going to be more likely to rust and fall off than a proper weld job.

Muffler Replacement on w124
 

Both new mufflers that I installed on my 92 300E w124 were Eberspaecher and are MB OEM parts. They look good, sound good and were only a few $ more than the competition. The units that I replaced were OEM on the vehicle and after 16 years were starting to develop pin holes. Go for the best.

tarheel75 :)

92 300E w124 110k "Black Pearl"

part number?
 

Thanks for the input guys.

It seems to be difficult to put chrome tips on the end. The tips at the muffler shops are all too long, and therefore they will stick out too much. Also, I was not aware of this issue that Jim brings up. Sadly, it looks like that I am going to have to forget about the dual chrome tips idea. A shame.

Does anyone know the correct part number for the 1990 300E? The one i got from the dealer is: 124 491 0400
But the existing one on my car is: 124 491 1501 3431 (these 4 numbers are written in smaller face).

I was wondering if the dealer gave me the wrong one even though I provided them with my VIN or did MB change the part number now?

Also, I thought these mufflers bolt onto the center one, but the muffler guy showed me that you have to cut off the rear from the center muffler, and bolt or weld the rear onto that point. I just thought there would be a place were it was bolted on, but it looks like a seamless piece right to the center muffler.

The original system is seamless and there is not joint between the center and rear mufflers. The replacement parts have a slip on joint and clamp.

On my 1992 300e, I had to cut the pipe with a hacksaw and then the replacement rear muffler fit right onto the cut off pipe. The critical thing is to cut the pipe in the correct location. Before taking the old system apart, measure carefully along the pipe and also hold up the new part and eyeball it. Don't forget to leave a couple inches extra to instert into the new joint, then check again.

Exactly correct. My experience with 1992 300E and and 300TE was just as outlined above.

Chrome Tips
 

Forgot to include this on my last post.

I added stainless steel tips to my replacement muffler very inexpensively and really dressed it up. I found a short piece of stainless steel exhaust pipe for sale on Ebay that was the correct size to slip over the muffler tips. I cut the the pipes at about a 3" length and at the OEM angle.

The tips were not very nice looking so I filed the cuts to round them off, wet sanded the pipe and then polished it with rubbing compound to a mirror finish. They fit a bit loose over the old tips so I glued them on with a bit of Hi Temp RTV sealant. That was about 5 years ago. Now every time I wash the car I wipe down the exhaust tips and they make the muffler look new again.