[2002]

Please reply with the material used for the brake pistons in E92 calipers.

Is the piston metal or fibrous like some newer designs?

Is there a source for new pistons - most parts suppliers I have searched show only gaskets and dust covers for rebuilds!

Steve

[Efthreeoh]

I'd bet the piston is metal.

The P/N shows the seal, piston, and dust cover:

10 REPAIR SET BRAKE CALIPER 2 34116769090 $25.42

This P/N fits the E92 328 and 335. This info is from RealOEM.com

[BillionPa]

10 does not include the pistons

when i pulled my pads off, the piston seemed to be metal, probably steel

[2002]

Thanks for the info. I was hoping BMW would have changed to newer material that doesn't rust. Anyway, I now know - thanks for your wisdom!

[BillionPa]

They made stainless steel replacement pistons for E36 race cars back in the day, but generally you can do better with special coatings now.

Xylar coating on a forged steel piston will not rust ( I do not know if they are factory coated, but that is what you should do if you want no rust )