Are the brakes somewhat spongy in the 231 or is the pedal high & hard?

 

For what it's worth, my 550 brakes are solid, and firm. Not sure about the "high". I've been doing a lot of mountain road driving and they've been excellent. Even on the long downgrades they don't get soft in any way.

If you do have a "spongy" issue, I'd check your brake fluid. How old is it, has it been "worked" on, and so forth. Spongy usually results from air entrained within the brake fluid. Brake fluid is not compressible, while air is.

On my '73 Pantera this was an issue until I did a reverse flush (applying pressurized fluid at the calipers, rather than at the more usual master cylinder). Once I did that, I got all the air out of the system, and it's brakes are as solid as anyone could want.

Hope this helps,

Chris

 

I didn't comment earlier because I wanted to do some testing. Mine are fine, hard and reasonable distance from the top...they seem excellent as a matter of fact. I have the AMG wheel package and I think that the brakes are different as well....so maybe that is part of it if you don't have the upgraded 19 inch wheels. I just checked MB's web site and "the 19-inch AMG wheels of the Sport Wheel Package reveal upgraded brake hardware that includes larger front discs, perforated rear discs, and "Mercedes-Benz" lettering on the front and rear calipers." - so the brakes are indeed different

 

I had the calipers painted red & that is when my problem started. I had them bleed the brakes & all is now good.