Brake noise..........

[Mr Noble]

Every time I brake hard on the road (worse on track IIRC) all is well for about 2-3 seconds then a really loud buzzing/wirring noise starts to resonate from the front brakes. Its always done it and I left it till the service and asked for it to be checked. I assumed it was the pads that needed replacing but was told they are fine and that the brakes are fine; but it still does it.

Is this normal?

GN

[AMG Merc]

Mr Noble said:

Every time I brake hard... ... a really loud buzzing/wirring noise starts to resonate from the front brakes.

Have you mislaid any family pets?!

Sorry but I just couldn't resist!

[DanH]

Not normal no. Don't let your dealer fob you off!

[Ash M400]

I had the same in the M12 and the M400 does it. It is normal.

Only time to worry is if you hear squeeling sounds, like metal to metal, by that time its too late, or if the pedal judders under your foot.

Then go back and look for threads on warped disks.

[chillidog]

Greg, have a look at the pads to see how much material is left.

Have you done the several heavy stops from 100 mph to scrub off pad material on the disks? ... obviously don't do this if you think your brakes really aren't working properly.
--
Richard

[Mr Noble]

So who am I to belive, Dan or Ash?????

There is no judder, and they do stop me pretty hard but the noise is a bit disconcerting, especially to passengers!!

Other consideration is that its my cars 1st Birthday today so the warranty runs out in about 13 hours!!

GN

[Mr Noble]

Richard, Its just had the 6k service at Kerridges, they seem to have done a good job and looked after me well but said the brakes are fine.

On another point, is the 6 k service, really just an oil change and general check over?

GN

[chillidog]

Mr Noble said:

On another point, is the 6 k service, really just an oil change and general check over? GN

It will also include new spark plugs.

[Mr Noble]

All for 6-700 squids. Blimey, glad I got it as part of the purchase price.

[Mr Noble]

Spoke to Bob at factory who is concerned that ist not a normal sound. Now booked in for them to look at in 10 days time.

Also booked in at Auto interiors across the road to have a pump up lumbar support fitted to the drivers seat.

GN

[DanH]

Hmm it may be normal, it just depends what the sound is. I think the front disks are floating on bells, and whilst these allow the discs to expand when they get hot (good), it does make them a bit louder.

Theres an article on PH front page about new AP discs with a different mounting to get around this issue.

[Mr Noble]

I can't see that anywhere Daniel. I do wear glasses but hope I am not just being blind. Link please matey!! Thanking you. GN

[DanH]

www.pistonheads.com/news/default.asp?storyId=10539

www.apracing.com/roadcar/brakekit/stdrive.htm

[Mr Noble]

Oh yea.

Thanks DH

GN

[Ash M400]

I am with Dan on this.

Depends on the sound.

I find this hard to explain, but it is like a loud grinding noise, unpleasant, but only when braking really hard.

>> Edited by Ash M400 on Thursday 5th May 23:31

[ThatPhilBrettGuy]

Not the splitter running along the ground or wheels touching in the wheel arches? Mine did this on grippy surfaces and maximum brakes until I had it raised a bit.

[Ash M400]

I think it is more like a groan which would rule out the splitter and wheels rubbing the wheel arch.

Told you I was not very good at this.

[paulcundy]

ThatPhilBrettGuy said:

Not the splitter running along the ground or wheels touching in the wheel arches? Mine did this on grippy surfaces and maximum brakes until I had it raised a bit.

This much dive surely not right?

[joust]

Ash M400 said:

I think it is more like a groan which would rule out the splitter and wheels rubbing the wheel arch. Told you I was not very good at this.

Not sure if the wheel arch or splitter should ever get near the wheel / ground!

Could be a few things. The pads could just need reseating. They are held in place by two "spings" at the top and bottom of the pad, and if these get out of place they make quite an effective noise source.

As the disk is "floating" it could be slightly out of true and generating noise between the wheel, disk and hub I suppose. Crud caught on the "face" of the wheel can sometimes cause funny actions from the brakes - ensure that it's all clean down there.

Finally, check you have the nuts done up to 130Nm - preferably with a torque wrench. Ensuring all the nuts are done up to the same torque is also generally a good idea.

Without really hearing the noise that's all I can suggest - as it's off to Bob you could check the above and if not, let them sort it out.

J

[Mr Noble]

It is not the clam or splitter rubbing. As I say, its just been serviced and I was told that all is well, but I don't like the noise much and passengers get slightly worried when they hear it.

Not really a grinding but a resonating humm of low pitch. Hard to explain but definatly not normal.

I would be shocked if the factory and AP racing were happy with their brakes making that noise, and the reviwers like J clarkson would have certinally had something to say about it if their test car did it!!

Will let you know the outcome on the 16th.

GN