Questions about rebuilding 1986 W126 rear brake calipers - PeachParts Mercedes-Benz Forum

mikeyfev1 · #1 06-05-2021, 02:39 PM

Hello everyone! I am rebuilding the rear ATE calipers on my 1986 300SDL. I have run into some issues and wanted to ask for help.

I need 2 new caliper pistons. I checked, and the host of this forum does not list them in their online catalog. So I went elsewhere and found another site that sells Centric pistons. I bought them and then found out that they have no lip to retain the dust boot! How can this ever work? The first time the piston retracts the dust boot will just slide off of the caliper! Does anyone know of any source for these pistons (other than the $$$s ones from Mercedes OEM sites) that are made correctly?

And I'm confused about the pressing surface of the pistons. One source says that pre-1976 rear pistons have a notched pressing surface and post-1975 ones don't have this notch. The pistons that I removed from my car all have the notched pistons. And it appears from the pictures that all of the replacement pistons that are available are notched. Should I look for the smooth pressing surface pistons? What's the purpose for the notch? Are the same calipers used for both types?

Thank you for any help you can provide.

Diesel911 · #2 06-07-2021, 04:53 PM

Quote:

Originally Posted by mikeyfev1

Hello everyone! I am rebuilding the rear ATE calipers on my 1986 300SDL. I have run into some issues and wanted to ask for help.

I need 2 new caliper pistons. I checked, and the host of this forum does not list them in their online catalog. So I went elsewhere and found another site that sells Centric pistons. I bought them and then found out that they have no lip to retain the dust boot! How can this ever work? The first time the piston retracts the dust boot will just slide off of the caliper! Does anyone know of any source for these pistons (other than the $$$s ones from Mercedes OEM sites) that are made correctly?

And I'm confused about the pressing surface of the pistons. One source says that pre-1976 rear pistons have a notched pressing surface and post-1975 ones don't have this notch. The pistons that I removed from my car all have the notched pistons. And it appears from the pictures that all of the replacement pistons that are available are notched. Should I look for the smooth pressing surface pistons? What's the purpose for the notch? Are the same calipers used for both types?

Thank you for any help you can provide.

There is a Centric brake parts company site. If you have time write to the and the company that makes them.