Brake noises and problems

[ChrisVee]

I have recently bought the RS4 it has quattro gmbh brakes front and back. Newly fitted for 2000 kilometres.

When I brake and am coming to a halt there is a whirring like rumbling noise, like if you blow through your mouth and vibrate your tongue. As I am coming to a stop it gets louder. Is this normal? It is like the pads going over the holes in the disks.

Also, if i drive slowly over small vibration bumps in the road, I hear a light metal rattle at the back brakes like they are loose. Is this correct? I could not see if the front ones are screwed.

I did take the wheels off to see if i can see something. I see the back disks ae not bolted to the hubs. They are loose and only tight up when the wheels are put on.

Can someone help me with the whirring noise and the rattle.

Thanks you

[Andiroo]

Hey Chris welcome to RS246 [img]images/graemlins/laugh.gif[/img]

Are you using OEM pads on the front? It could well be the the OEM pad is not up to heat generated by the GmbH disc and a bit of glazing on the pad is making the noise. I wouldn't have thought it would be a warped disc as this is not very noticeable at low speed/stopping.

As for the rears, take a photograph of your hub/disc and post it up - not much to go on till we see it mate [img]images/graemlins/wink.gif[/img]

Btw what wheels do you have fitted ?

Andiroo

[JJRS4]

Rumbling and rattling doesnt sound good to me. Look forward to some pics.

[ChrisVee]

The pads they are yellow Pagid that are part of the quattro brake kit. My wheels are standard rs4 wheels.

I have taken the pictures and ask the webmaster to show them in my message because i do not know how.

[Andiroo]

Chris, my first response is the Pagid Yellow pad - for the GmbH option you are using too hard a pad. These pads need warming up for use and will squeal and vibrate if not regularly degalzed @1k miles. They are basically a race pad (which I use on my Sportec 4-pot 380mm) and you have no chance of making them good for the road [img]images/graemlins/frown.gif[/img] IMHO go with a softer compound, if Pagid go for Blue [img]images/graemlins/thumbs.gif[/img]

We will wait for your photos and then comment on your rear brake issue [img]images/graemlins/wink.gif[/img]

Andiroo

[JJRS4]

That is very interesting Androo. I was told that Pagid yellow are the standard pads with the gmbh brakes.

[Bushy]

The paggid yellows on the GMBH kit is a nightmare

I had this very set up and the front discs only lasted for 6000 miles before becoming warped

I changed the front to Movit and the rears I left with OEM pads, the paggid yellows IMHo are just too hard and abrasive so under heavy braking generate excess heat which can cause excessive wear and also the discs may warp

Just my opinion, but I reckon the cross drilled rotors will be better at reducing heat build up and should work fine with OEM pads

Hope this helps

Bushy

[Andiroo]

Here's a link re some Pagid compounds here

Andiroo

[Bushy]

LOL, it always worries me when the brake manufacturer says it has good fading qualities [img]images/graemlins/033102scull_1_prv.gif[/img]

Surely they dont mean it is good at fading [img]images/graemlins/033102bad_1_prv.gif[/img]

Sorry just my sense of humour, I will shut up now

[ChrisVee]

I do not know why the webmaster has not shown my pictures that I did email him. Can somebody else help me?

I said before that the disks front and back are not screwed to the hub. When i take the wheel off the disks can move. Is this correct? Is my car safe?

[Andiroo]

Hey Chris you're car is perfectly safe [img]images/graemlins/thumbs.gif[/img] When the wheel bolts also hold the disc in place, this is called a floating hub, like my Sportec ones, which allow the disc to expand and contract under heat tolerances. Although your problems are of concern.

Where did you mail the photos, coz you can simply put them in the Gallery if you so wish [img]images/graemlins/wink.gif[/img]

Andiroo

[ChrisVee]

I thinks the web master is asleeping

I have made the pictures in the galary. i hope this is okay and you can tell me about the whirring and rumbling.

Brake pictures

[Riz_RS4]

Where those disc`s and pad`s fitted new from 2000kmls?

They look very bad. [img]images/graemlins/033102bad_1_prv.gif[/img]
I would see what the RS4 members have to say as i dont have a RS4.

Riz

[Bushy]

Exactly how mine looked after some very heavy driving and 6000 miles, IMHO they are no good and all the problem is casued by the Paggid pads, they just destroy the discs

I now have the Movit 4 pots with 380mm discs on the front, and put standard pads in the rear with the cross drilled discs

I am afraid they look like they need replacing

Cheers

Bushy

[Andiroo]

Bad news I'm afraid Chris [img]images/graemlins/frown.gif[/img]

Looking at the front dics photos they are very worn and I would recommend immediate replacement IMHO.

It also looks like you have either a warped front disc or the caliper assembly needs aligning - look at "Front Brake 3", the pad is not aligned to the disc evenly from front to rear.

The rear discs look in lot better condition as they should (brake bias is too much front not enough rear on the RS4), although it's hard to tell the condition of the pad from the photos. The rear noise could be the rear disc shield being loose, or even an exhaust mount which is quite local to this area.

All in all, new front discs, Pagid Blue pads front and rear, and both front and rear caliper assemblys serviced IMHO [img]images/graemlins/wink.gif[/img]

Good luck and keep us posted,

Andiroo