Why clamp exhaust instead of weld?
 

Got my OEM rear muffler and clamp for my 92 300D....not going to mess with it myself but am just going to take to exhaust shop.

Just curious: why, by design, does MB have exhaust components held together with clamps? Is there something in the production process or some other reason why this was done as opposed to welding?

The shop will do whatever I want but I'm sure will recommend welding. Just wondered what MB's rationale might be.

I've never heard of any car manufacturer welding exhaust components, other than maybe a custom shop piecing together a header. The reasons:
1) Ease of assembly.
2) Ease of repair
3) Cost of replacement parts If they had welded it together, you'd be replacing the entire exhaust at this moment.

For these same reasons, a shop would be nuts to weld your exhaust, especially if its a new piece going on an old pipe.

Partly welded exhaust has been common on American cars since the 70's. Depending on how the car was assembled, at least the tail pipe was welded to the muffler and sometimes the pipe just ahead of the muffler too. When any part of this welded assembly needed replaced, it was usually a replace all 3 parts. Sometimes a pipe could be cut and muffler installed. The factory prewelded system eliminated the need to adjust pipes to fit and is much faster to install.

As for what to do now, If the joint needs to come apart to take suspension apart don't weld.

It doesn't really matter on a car with IRS. The exhaust is more or less flat other then the down pipe to the engine. From what I have seen MB has a down pipe section that goes from the turbo/exhaust manifold to just the rear of the transmission. then there is a flange. Then a second section that goes the rest of the car. The pipe is just bent so that it is in the right place when hung.

Most import cars are welded with flanges around different assemblies (down pipe, catalytic converter, down pipe, ect) Most domestic cars used different sections of pipe that are sleeved and clamped together. You'd think the welded and flanged exhaust systems would be harder to repair, but not really. The sleeve and clamped connections are clamped so tight, then rust, making it so you can't unsleeve them for service. This is why all exhaust shops weld, because they have to cut out sections of exhaust that will not come apart.

I bet your exhaust shop will weld as needed and will reuses the stock flanges and leave them in their current locations.

A repair shop may use an oxy torch to cut away a rusty sleeve. And flanges are easily separated and rejoined. But if I ever saw a tech welding an exhaust component onto one of my cars, I'd put that torch where the sun don't shine. It's an irresponsible act of vandalism.