I worked on the rear brakes on my 83 300SD, 250k

New rotors, new pads, one new caliper. I put plenty of the orange goop on the back of the pads. I've done many brake jobs in my past, but this is the first MB.

Very soon after, I noticed squeaking on light braking. It goes away if I press hard.

Any words of wisdom on possible idiosyncrasies of the MB braking system?

Thanks

Mark in MA

I the same problem on my car. it comes and goes. the cheap and easy way to make it go away and to wash the rotor with water and that will let a little bit of rust build up on the surface. it will quite that squeek. or if you have the wheels off hit the rotor with some sand paper, or scotch bright pad.

the squeek is the result of smooth rotor and smooth pad. the mercedes seems to have this issue more then other cars... i don't know why.

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it's the hard surface of the rotor and the soft pads that MB uses...
I always use 220 grit paper on the pads with a power sander, the vibration kind, not the orbital kind...
John

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Try shims. That's the ONLY thing that worked for me. Including cleaning, sanding, and goo-coating.

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1989 300E 144K

I'll try roughing up the rotors.

Thanks for the info.

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Mark in MA
05 MB E320CDI 402k Granite Grey Metallic
05 MB E320CDI 267k Black
05 MB E320CDI 232k White
05 MB E320CDI 209k Tectite Grey
99 Dodge 2500 Cummins 5sp 148k
62 Jeep CJ-6 120k

My brakes squeeked loudly and horribly when I got the car. Pads were brand new. Took off the pads, filed the edges of the pads to round them off, greased the backside with some silicone high-temp break grease, and problem went away...

Until I took the car to my indie, who took it upon himself to fix my brakes for me (the wear light kept going on after I forded a stream the week before) by replacing the sensor wires. The sensor light stays off now, but now they squeek a little. Someday (hmm.. like maybe tomorrow while I'm finishing the UCAs) I'll regrease the backs of the pads and see if that's the problem.

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'83 300DTurbo http://badges.fuelly.com/images/smallsig-us/318559.png

Broadband: more lies faster.

When I did the brakes on my 240, I used the same process I have for years on everything, hand spin the rotor at a mild rotation and use a right angle air die grinder with 3M Roloc rubber backing pad and a medium grit 3M Roloc pad, put an even light finish on the rotor, helps to seat and wear in the pads to the rotor & avoid glazing, and never squeals, or pulls as long as you do both rotors the same. (Poor man's rotor turning job), works great as long as the rotors arent in a good need of refacing due to warpage/uneven wear/ deep grooves. If there is a ridge on the edge of the rotor I first use a coarse grit pad and grind the ridge down flush to the worn surface. I wire brush all slide surfaces and use sil-glyde brake grease, wire wheel all caliper pins and use the same grease. Never had to apply anything to the pads in addition to the anti vibration plates that come with them.

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Chris
64 190D R.I.P.
80 240D W/617 engine -for sale
82 240D -for sale

A trick an old Indian Scout once taught me is to use a file to put a small 45 degree edge on the face of the pad -- I've cured a couple of squeals that way ... I guess it makes the leading edge less perfectly sharp & prone to grabbing ---