W115 Rear Window Seal Replacement
 

Is replacing the rear window seal something I should consider DIY or should I let a glass shop do it? My son has volunteered to help. Water is leaking into the trunk of my pristine 1974 240D. Fortunately we are now into the dry season here in FL so rain isn't so much of a problem right now.

I have read many a horror stories about DIY window replacement projects, especially on the W115. My advice would be to take it to a pro, you may find with even that they may not be willing to take on the job. Good luck

Buy the seal direct around 20-40 dollars. Bring it to a shop and have it done. Do not do it yourself. If the glass breaks you are (*&^%ed.

While in the shop may want to have the front one done two. I had both mine done for $100 a window, I provided the seal. 1977 300D, 123 chassis but similiar in application. I brought it t a Diamond Auto they did a good job

Regards Tom

Don't Worry, it could be easy, or, maybe not
 

I replaced the same gasket around my back window on a 1974sel just last week. I had water leaking into my trunk which created several other things to clean up, and thought replacing the gasket would end this.
The problem you might find once you get the back window out is that beneath the rubber is a natural catch basin for water which stands.
Once I had the window out found that some patching of the rust which had eaten holes through the metal near the lower corners of the window frame, where the water was actually coming in, became necessary before placing the window back in. While the glass was out was a good time to replace the material in the back shelf which had also rotted out due to the water. And water had leaked under the back seat and created more mess to clean up. It turned into a real big project. To get the new gasket in easily, remove the interior trim above the doors and back window and remove the back seat and hat shelf to make the frame accessible.
Mine is done now, and looking at it with the new gasket is as satisfying as having a new car,,,,,almost.
If you are a DIY'er, go for it. If you need any support, e-me.

W115 Rear Window Seal Replacement
 

With the comments I have received, I don't think I will attempt the job. Right now the car is my everyday transportation so it would have to be a task that could be completed in one day. I think I will just replace the rear flex brake hoses instead. I will shop the window seal replacement around to some of the local auto glass shops.

If it needs to be a day job, you made the right choice, just make sure where you take it has done some before:)