I need help on getting rid of brake squeal on 89 300e
 

Can anyone give me advice on how to get rid of brake squeal on my 89 300e. I replaced the pads (front and back) a couple of months ago. I think it's the back wheels that are squealing, and it's usually only under hard braking.
Any advice would be great.

Mercedes sells a paste that is to be applied on the back of the pads to prevent squealing.

I think it is actually called anti-squeal paste.

It goes without saying that original MB pads are the least likely to squeal. All other aftermarket pads cause excessive squealing.

In addition to the excellent points made by Paul, the initial break-in period is extremely important for long, quiet life of MB pads. The recommended procedure is is to make 5-10 easy stops from about 30 mph, but letting the pads and rotors cool off between stops. A lot of people neglect this step and are left with pads with little hard, burned high spots which can be noisy.

Some say you may be able to counteract this with a number of hard stops to break up any glazing on the pads.

When installing pads (best to use OEM ones from Padgid, Textar, etc), always clean the slots in the calipers completely of rust, corrosion, or old brake dust. Otherwise, one side can be tighter than the other, allowing the pad to vibrate.

Also, coat the piston contact area, the sides of the backing plate where it touches the caliper, and the spring where the retaining pins sit with some antisieze. This will prevent a large amount of squeal.

Breaking is required, and the brakes will be somewhat less effective when initially applied. Fur on the surface from machining, I think.

To fix your problem now, pull the rear pads and apply the antisieze, and take some coarse sandpaper and rough up the contact face of the pads. Re-install and do the break-in again.

If you are using PBR Metalmasters, either change them to OEM or live with the screech, if they squeal on your car, they will always.

Note that the lastest models, mostly C class, from MB have a known problem with squealing rear brakes -- no solution yet, as even new calipers won't always fix it.

Peter

Very simple! Turn up the radio volume. The squeal doesn't hurt anything.

Good luck,

SHAWN

I had terrible brake squeel from the rear on the 190e after brake pad replacement.

I did all the above suggestions but still the squeel. I noticed the disk surface was not as smooth as it should be.

I had the disks re-surfaced and the problem never came up again. I use PBR Deluxe pads all around.

It has been suggested not to turn/resurface Mercedes disks but in this case there was still enough thickness (after turning) so I tried it.

Haasman

An alternative would be to take an hack saw and cut a cross groove across the pads. This will shorten the frequecy of the sound wave so that only the dog will hear it.

The downside is that a howl replaces the squeel.

:)

I had this rear brake squelling problem with my 84 500SEL with Pagid pads. I installed brake pad shims and antiseize compond and problem gone.

I have PBR Delux in the rear with new Balo rotors. No squeel what so ever. I used brake pad paste with no shims.

Haasman said,
I had the disks re-surfaced and the problem never came up again. I use PBR Deluxe pads all around.


Many shops will not turn rotors due to thickness requirements. I paid $27.00 for my Balo rear rotors ea. What did they charge to turn them?