Car sat for a month, now warped front rotor?
Battery on my caliper died, but its still a bit over 30mm

I wasn't exactly square on, it might be right around 29-31mm?
I found MB P/N A 1714210112 on the driver-side rotor. Should be ordering new ones tomorrow.


You will likely never mount up another pair.
5k miles since I paid big $$ to have mine turned and they are doing their job as designed...
While you have the pads out scuff them across some emery cloth also to remove the rust imbedded in the surface of the pad.
Again soft pads will not clean off rust on a rotor.
Good Luck, do not buy rotors just yet, you will be surprised at the surface on the back side of the rotor.
Your old rotors did not even show a lip, they could not have been that used.
The Best of Mercedes & AMG
cm60k: Not sure what to do with the old ones, they're too friggen heavy to make a clock or something out of.

I did notice the old pads were not making the best contact with the new rotors so I ordered new pads too $216.95 MB P/N 005-420-39-20 from getmercedesparts.com (same place I got the rotors from)

Back side of the rotor with old pads since Critter asked:

The inside (back?) pads were making better contact than the outers on both sides.
Anyway, new pads came in today, here they are on the old rotors:


They're about twice as thick as the old pads.
I moved the wear sensor over and fought with the pistons trying to get all 3/per side moved back at the same time. Ended up over-flowing from brake fluid from the reservoir
but got it all done.Sadly, there still a tiny bit of 'wobble' under heavy braking above 70mph. But under 40mph (which is 90% of my driving these days) it is back to normal.
And you can see after just 20 miles the whole disk surface is being swept again:


The price of the new rotors would tempt me to resurface them if well within the min thickness. Ask a rotor shop if they have the ability to stress releive the warped rotors.
As you have stated this new rotor setup did not actually resolve your issue, now look at the rear rotors and you will see the same start stop issue as with the front.
In the picture these rotors have minimal surface wear


As you have stated this new rotor setup did not actually resolve your issue, now look at the rear rotors and you will see the same start stop issue as with the front.
In the picture these rotors have minimal surface wear
unpainted concrete floor, but yes you are correct. Crocus cloth/pads works well on surface rust on rotors as they do not remove the steel surface but only the rust and glaze.
I'm going to pull the front pads tonight and put some anti-squeek on them, I'll measure.
I took the car to Belle Tire, explained how much the new ones would be and asked if anything could be done. They said they were too thin

Critter:
The heatshield/splash guard covers most of the back of the new mounted rotor. I'd have to take it all apart again for a better pic, sorry.
I'll get some better pics of the old rotors too.
I haven't even looked at the back wheels yet to see if they're having the same issue.
Edit:
new pics!
Sexy fully swept rotor:

New vs old pad pics for dave2001



Goddamn squeaking was driving me nuts
Last edited by ambit; Feb 11, 2014 at 06:31 PM.


From the old rotor pictures, it was about 32mm thick and about 34mm for the new rotor. Am I eye balling correctly? What the min. thickness which should be molded or stamped on the old rotor?

New discs have been great. Couple thousand miles on them and 1 track day. No issues front or rear.
But now the A/C is hissing











