soma

I have a 2003 C230 sedan. About 6 months ago the brakes started squeaking during light and medium braking. I took it to my dealer and they said I still had(at that time) 50% of my brake pads left. I can't really remember what they said was causing the squeaking but they offered to put on "brake paste" for $200. I declined since they told me it might only last for a few months.

Well, the squeaking is really starting to annoy me now. Let me also point out that I have 35,000 miles on the car and have never had the brake pads or rotors replaced. I would say more than half of those miles are highway, so I'm assuming that is why I have gotten so many miles out of them.

My questions are:

If the brake pads are ok, what is causing the squeaking?

Can brake paste solve the problem?

How much should I be charged for new brake pads and do the rotors have to be replaced as well?

NitrogenBalance

From the 35,000 and the highway driving I'm sure you rotors are fine. You may get well over 50,000 out of them. Actually, to answer the question better I would just jack the car up, remove a wheel, and check the rotors. If you have an open wheel desigen you can do probably without removing the wheel. My car has mononblocks and you can't get the best look or feel through the small hole.

I don't know what the dealer cost of pads would be, but pads for all corners shouldn't cost over $160.00 for sufficient qualiy. You don't need high temp race pads or anything. What they charge for install I have no idea. Benz dealers around here are about $95ish an hour for labor.

Also, the squeel paste is a few dollars. I'll put it on for $200 wearing a woman's dress. $200 to install that paste seems insane to me. DIY...in my opinion.

mleskovar

If the brake pads are ok, what is causing the squeaking?

The squealing is caused by the brake pads vibrating between the rotor and brake piston (someone correct me if I'm wrong in my explanation).

Can brake paste solve the problem?

Yes and maybe. Depends on what's causing the vibration and if lubrication between the piston and pad is sufficient to stop it. Sometimes it's a combination of humidity/heat/usage/wear. I've never read a definitive answer as to why they start and stop squealing. Sometimes paste/lubrication works and sometimes it takes several applications and sometimes it doesn't work at all until you replace parts.

Moviela

Farmer John uses the whole pig in their operation, and they sell the squeel to ATE and Textar. Have you considered ear protection muffs from a gun shop? At least you won't hear the squeak anymore. (J/K)

I find that cleaning the dust and dirt from the machined "ways" that the pads slide on helps. You have to return it to an 'as new' surface, which can mean lots of elbow grease to get the stuff off the metal.

Next, I use a dial indicator to check the runout of the disc. Anything more than .001 means the disc must be machined. The disc makers don't put much extra meat on the things, so turning may be a waste of time, or dangerous.

What works the best for me is double sided tape from 3M. It is not the thick foam stuff, but a very thin, clear material. It is intended to hold trip pieces on car bodies. I put it on the rear of the pad, so the pad sticks to the piston. This works quite well. When the piston retracts, it pulls the pad with it.

I have had cases where only one wheel squeaks. This was caused by the piston getting stuck partway out. Cleaning and replacing the caliper rubber solves the problem. Usually when it gets this bad, it is because the brake fluid was not flushed, and the brake dust has contaminated the system.

There is a lot of discussion about rotors and cross drilling and milling slots. I assume this is a street car, so the advantages of cross drilling are only that it looks cool. Milling slots, however, can be helpfull. They act like a blanchard grinder to keep the surface of the pads smooth. This results in greater contact area, and better working brakes.

jeremy

take a look at your rotors. If you see a small lip on the inside edge and outside edge, you may be experiencing the same problem I had. It seems that the brakes do not extend to the edges of the rotor and, after a little use, create these edges as they wear the rotor. The pads then vibrate between these ridges and cause the squeal. The fixes are (1) have the rotors turned (on the car is much cheaper) or have the pads rounded on the edges so they don't vibrate between the ridges. These may not be MB factory approved solutions, but they cleared up my squeal. You can have the rotors turned a couple times before they become too thin to dissapate heat efficiently (and warp). Also, if you are getting ready to need new pads, explore some of the different materials being used in pads (heavy duty or ceramic)... Good luck!!