Brake Squeal

[75coupe]

Actually i remove all calipers and clean them thoroughly, paint them before going back on, cut off stone guards if tracking it, braided lines, brake cooling ducting, decent pads research that, decent slotted rotors research that, keep shims or get new project mu shims some pads have rubber backing or sticking backing, research that, get some copper grease, research that... See i can get carried away

[kingtube69]

Thanks coupe, I would love to go that crazy but I think I should stick to braideds and fluid for now

Changed the rear pads over the weekend, no squeal at all.

[sonicz]

Something I have never heard anyone else say, but I have found purely from personal experience is worn wheel bearings (even the tiniest play) can cause brake squeal because it allows the rotor to move imperfectly in relation to the brake pads. This causes uneven wear and after a while a squeel. If someone is out of options its worth changing your wheel bearings, machining your rotors, installing new pads and seeing if the noise goes away.

Edited February 13, 2015 by sonicz

[75coupe]

You can easily tell if wheel bearings are worn...

[GTRPSI]

Usually worn bearings lead to brake shudder and disc thickness variation.

The disc moves around between the pads leading to uneven wear moreso than brake noise.

Ive seen cars with seriously worn bearing never make a sound, the only hint was bearing noise and then brake shudder.

[DN14]

took the r33 to another mechanic (works on alot of performance cars) it was apparently the rear pads, they swapped over the Bendix pads with Repco thermoquite ones & the squeak did go away.

now a week after it squeals again ..

imsomadritenow f**k

wat to do?

really considering selling the car after getting the brakes done by mechanics twice and 10 times myself just for it to squeak again

[75coupe]

The answer to the problem is written time and time again throughout this forum and many others, and also sarlier in this thread...

So your experiencing people that dont know brakes, dont give up.

Its not your pads, its not your rotors, its a high frequency vibration, go get some copper grease,

[DN14]

one thing i know is that its definitely not a copper grease issue iv used a kilo of anti squeal behind the pads aswell as applying copper grease without no effect

what do these marks mean?

http://i.imgur.com/kKX9wcv.jpg

http://i.imgur.com/8V7yyrX.jpg

iv only had these pads for less than 10 days now

[Hadouken]

I think you need to rough them up and then go bed your brakes in. And be mean about it.

Kind of looking like they are glazing.

I have no shims or copper grease and just put in a set of intima sr pads and have no squeel.

[DN14]

I think you need to rough them up and then go bed your brakes in. And be mean about it.

Kind of looking like they are glazing.

I have no shims or copper grease and just put in a set of intima sr pads and have no squeel.

thats the thing, even if that did get rid of the squeaking a week later it wil just rise again

i need to know the root cause of this

[niZmO_Man]

Roughen the pads up and bed in again.

[Missileman]

Roughen up the pads wit 80 grit and the discs with 240 and learn to live with the squeal, over time as the pad wears down don't be surprised if the squeal disappears.

[75coupe]

Squeal is vibration so if roughing them up doesnt allow them to stop the surfaces jumping around on eachother then you need some baffling to take up the vibration. Chamfer the leading edge of pad, if it still squeals then your shim rubber is very good

[GTRPSI]

Post 3 pictures.

1 of your assembled caliper looking into it so we can see how the pad assembly sits.

2 of all the shims, clips and pins being run taken off the pads and the back of the pads.

And 3 of the pistons faces in the caliper and the leading/brakeing edge where the pads put thier force into the calipers.

Those pictures you showed of the pads show they were not bedded in yet, some pads make noise till they bed in.

[MozzMann]

Pad compound has a lot to do with squeal as it generated movement at a high frequency.

I cured many by making alloy slugs that fit into the piston and are about 1 mm thicker than the original shim, machined them down so they hold the pad dead flat and true on the rotor with no movement thus no squeal.

Remember you do not necessarily need to bed brakes these days ( Depends on the Pad ) and in some cases if you do you will over heat the compound resulting in hardening of the pad and reduced grip and more vibration thus squeal.

2 or more spots of Silastic applied to the back of the pad and pressed into place before it sets after allowing it to set this provides a tiny shock absorbing layer in a similar fashion to the PBR Squeal Stop solution.

[Dobz]

Those pads in the pic look normal, those scuff marks that run diagonally don't. Is that from roughing them up last time?

Have you had the calipers inspected for sticking pistons and have you checked the spring plates don't allow the pads to move up and down in the caliper.

[cashie484]

A lot of modern pads have these problems, ever since pad suppliers have gone from asbestos. Still can't get it right