930 new brakes squealing

[solarispete]

Hi fellow 930 experts,

I had my brakes done a few months ago - new Zimmermann rotors, new Pagen brake pads, calipers rebuilt (using original Porsche 930 kit), replaced some of the flexible brake lines, all in all over $3k
invested (including labor)...

The brakes have been squealing since I got the car back... Especially when I bring the car to a stop lightly. It doesn't squeal when I stomp on the brakes.

My mechanic has even replaced the Pagen pads with Textar, but same problem.

At first, I was told that it will wear out and go away after a few hundred miles, but 4 months later
still squeals and it's annoying...

I have asked my mechanic for more suggestions. One thing he suggested was to glue the back of the pads to the calipers. He says some Mercedes does that. I spoke with another mechanic who told me that there's some sort of lube to put between the back of bad and caliper, but it's not glue.

Anyone have any suggestions?

Peter

[Niels]

....the rotors are directional, make sure they are spinning the right way, seen it done on a 928, squealed like a pig

[Miguel Antonett]

Do they continue squealing after becoming hot?
Those 917 brakes like action... use them and the squealing should go away - assuming proper installation to start with.

[mark houghton]

Originally Posted by solarispete

I spoke with another mechanic who told me that there's some sort of lube to put between the back of bad and caliper, but it's not glue.

Anyone have any suggestions?Peter

I believe that is true, for any car with disc brakes and if I'm not mistaken most pad kits come with some sort of lube (I seem to remember doing my Toyota brakes years ago and it included a tube of lube "stuff"). I don't understand how/why it works to prevent squeeling, but apparently it does.

[Hirevtuner]

A couple years ago I replaced all my rotors and put performance pads on. As I recall there was a break in procedure that would allow the pads and rotors to mate up and prevent noise and pulling. It was something like pin it to 30mph then come to complete stop a couple times then pin it to 60mph the come to a complete stop a couple times then park and let it completely cool down. Anyways I followed directions and have had no problems. Maybe check with the manufacturer of the pads on there break in procedure.

[Hirevtuner]

Oh ya and I did not use any of the blue or red lube/glue that is used sometimes.
I have used it on lots of brakes but I was told by the manufacture of the pads it was not needed.

[gsxrken]

Google for stop-tech brakes and their brake bedding-in procedure. Pads need to deposit a layer onto the rotors for effective braking and less squealing.
It's a great website to learn more about brakes than you knew beforehand.

[full quack]

Brakes squeal for 2 reasons, pad face to rotor contact & backside of pad to caliper piston contact.
The blue or red anti-squeal compound is supposed to stop the pad to caliper piston contact squeal {there are also plastic shims you can buy for this as well}.
The pad to rotor squeal is more difficult to eliminate. The biggest culprit is the pad compound selection. The higher the intended operating temperature of the pad, generally the higher the tendency to squeal with light or even no pedal pressure.
Pagid "blue" pads work well for me on the street, "orange" squeal like a banshee, "black" squeal slightly with light pedal pressure applied.

My experience & my .02 worth.

Mark

[EluxT]

One might try slightly chamfering the leading edge of the brake pad with a flat file. Works now and then. Ancient trick.

[Gus Berges]

You have all that you need to solve this: chamfering, proper installation of discs, proper bedding in of pads, anti squeal grease, and anti vibration dampers for the pads. Make sure you have clean surfaces (discs and pads).

[solarispete]

thank you so much for the wealth of information!

But, no one has heard of gluing the backside of brake pad to the calipers? This is what my original mechanic offered to do... He says he does that for Mercedes.

[full quack]

I would not be gluing anything to anything, that is just plain WRONG. I don't care what halfa.. mechanic claims to have done this on a Mercedes.
No properly trained mechanic would ever do this, unless it is done out of ignorance or ineptness.
Find a new mechanic.

Mark

[TT Gasman]

Probably the Pagid pads, what kind are they?

[Mike80911]

There is also an anti squeal spray that you spray directly on the rotor and the front of the pads I have used it before on my Cayenne and it did work. I forgot the name of it but your local parts store should carry it.

[Dave 86 930 Fl]

Originally Posted by solarispete

Hi fellow 930 experts,

I had my brakes done a few months ago - new Zimmermann rotors, new Pagen brake pads, calipers rebuilt (using original Porsche 930 kit), replaced some of the flexible brake lines, all in all over $3k
invested (including labor)...

The brakes have been squealing since I got the car back... Especially when I bring the car to a stop lightly. It doesn't squeal when I stomp on the brakes.

My mechanic has even replaced the Pagen pads with Textar, but same problem.

At first, I was told that it will wear out and go away after a few hundred miles, but 4 months later
still squeals and it's annoying...

I have asked my mechanic for more suggestions. One thing he suggested was to glue the back of the pads to the calipers. He says some Mercedes does that. I spoke with another mechanic who told me that there's some sort of lube to put between the back of bad and caliper, but it's not glue.

Anyone have any suggestions?

Peter

Peter,

I would suggest that you go out on a local highway and run the car up to a reasonable speed and apply the brakes really hard. Do this three or four times and you will get some temperature in the brakes. As a result, you will bed in the new pads and rotors. I would not be surprised if you experience some vibration when applying the brakes ... Don't worry. After 3 or 4 brake applications, drive the car for a few miles in order to let the brakes cool down and then head home, using the brakes as little as possible. Park the car (no parking brake) and I'll bet all of your issues are gone by the next day.

Regards, Dave

[Gus Berges]

As stated before, regarding bedding in pads and rotors (especially when new), go to the Stoptech website and read a technical support whitepaper they have on bedding in properly new pads. Here is a link to it:

Stock Brake System Bed-in

[Jbp]

I think your brakepads is on the hard side and need a damper on piston side.
Your pads start to wibrait when you com to a stopplight in low speed.
Dampers is like a thin ruber to put on piston side of your pad.
An other option is to go for a softer pad.But this make more breakdust on your rims.
Hope this helps.


Jocke.

[solarispete]

thank you all so much for the wealth of info! I will go for a drive tomorrow to try out the "bedding" procedures discussed. Maybe it will go away after 3 or 4 tries!!!

much appreciate the responses!

[MT930]

I run Pagid pads (Orange) Track pads. They squeal, Great on the track I don't notice the squeal, in town.

Yea they squeal in town I don't care. I olny drive through town to get to the road.

[DohertyCM]

The pagids squeal when not on the track and hot.
The suggestion to ruf them with a file is what I do...or some rough sandpaper...this only works until you glaze them again...but it does work.
The next thing is try the grease that comes with the brakes...sometimes that works..
Vibration is a factor, some guys will not like this, but I use just a little high temp sealant on the back side of the brake and this will form a thin rubber gasket and help prevent the squeal...

Last thing...Jump to a hawk racing pad for street use....and save the high dollar pagids for the track.. My hawks never squealed..