993C4Smontreal

Guys,

My brakes hgave a crazy "howl" intermitently. The squal is gone..

Front: New pads, new Discs, vibration dampers..all OEM from dealer.
Rear: New pads (oem from dealer), refinished discs, new vibration dampers.

The howl is still there....Its annoying and embarassing....

I have spent $600 on just trying to eliminate the sound, and no success.
any ideas, please help?

TIA

Mike J

A few questions:

- is the squeal from the front or back?
- my understanding is Porsche disks are not to be machined but ground. In fact I think Porsche recommends that their disks are not to be machined at all. How were they done?
- Does the squeal happen cold or when the brakes are hot?
- Any pulling on the brakes?
- Are the calipers in good shape and have been bled recently?

In practically all cases that I have heard about, putting on the spiders, new disks and new pads (with the Porsche logo, it makes a difference) solved the problem. I am not sure what is happening with yours..


Cheers,

Mike

993C4Smontreal

Mike:

1)pretty sure the HOwl, not sqeal, is from the Back. (not 100%)
2) have to ask the guy that redid them. He says "machine".
3) Howl when cold and hot. more when hot
4) no pulling
5) dont know about the callipers.

TIA

Mike J

Ok, good if its from the back it could be the parking brake shoes or a bad bearing or...

Have you jacked the rear of the car up and tried to rotate the wheels to see if you notice any noises?

Is the howl always there, or just on braking, or hard braking, or coming off the brakes?

Cheers,

Mike

993C4Smontreal

Dr. Mike,

I havent jacked up the car....howl is there sometimes, and only on braking......more on slow light breaking. It is not there on hard braking.

Mike J

It sure does sound like the rear pads are vibrating since under light braking they can vibrate, but heavy braking will seat them in strong with the disk.

I am not sure of the next steps. You can replace the rear disks with Porsche new disks...that would guarantee that the disk surface is good, the pads are good, and it has new spyders. Like I said before Porsche does not recommend refinishing their disks, especially machining them. Its hard to tell anything more without being there...I would jump into my car and drive over but it will take me the better part of three long days....

Cheers,

Mike

CraigC

If you pull your pads and file the leading edges of your brake pads so they are round and not square it will probably get rid of the pad noise. Another thing you can do is go to the autoparts store and get some disk brake quiet to put on the back of the pads. clean the inside of your calipers with brake cleaner and scrub them out with brake parts cleaner and paper towels. All of these things will eliminate the pad vibration that is causing your noise.

mhm993

Dust shield noise?

Wilder

I was thinking along the same lines. Have you given your brakes a good wash? Take your hose and, with strong pressure, spray the disks/pads/calipers. Try to get all the dust collected in the drill holes washed off. They might squeal for the first couple of stops after you wash them but should be fine after that if it's just caked brake dust that needs to be cleaned.

Land Jet

Did you do a proper bedding in of the new brakes?