Brake Judder - Causes
 

Hi I have brake judder.
It tends to kick in when there is warmth in them and I am driving fairly hard.
I guess it is warped discs.

The car has been sat about for a long periods on and off over the past year. Whilst it has been worked on...could the brake fluid have moisture in it?

However that is what usually leads to brake fade not judder in my past experience.

Can brake fluid that needs changing cause brake judder? Is it worth changing before I look at the discs?

Any other suggestions as to what can cause judder?

Godspeed 335mm
Refurbished 4 pots
Braided hoses

brake fluid was stuck in when we did the braided hoses about 14 months ago
New alloy arms - ARB - ALK and droplinks recently gone on.

Thanks
Steve

It could be the pads but most likely as you have already suggested, its warped discs as the hotter they get the more distorted they become and the more judder you get :(

Tony:)

Ferrodo DS2500 pads perchance?

If so, it'll be them leaving deposits on your discs!

Yes spot NS04 on I have DS2500 pads on.

I usually run with pagid

So I need to change the pads.
These deposits that the Ferrodos kind of cook on, for want of a better expresion, does that mean buggered discs or can the deposits be removed?

If pads are leaving deposits then first thing is get rid of them. Then a good brake/carb cleaner should clean them up. If the judder is coming through the pedal then it will be disc related. If its coming through the steering wheel then its worth checking for a seized caliper!

Steve, I take it your discs are grooved?

Tony:)

Thanks Fieldy.
Will have to drive to confirm the feel
But from memory through the steering wheel.

Tony - yes they are grooved

Steve

In my experience mate the problem may well be a seized caliper! Only way to really tell is to take them off and try to rewind the pistons. if one is very stiff or even seized then there is the problem.
Spen

A proper "workout" should clean them up nicely....

IMHO

dunx

Mine vibration comes from through the wheel too. AP six pots (CP57....oh, the best ones!!) :) so very unlikely to be a seized caliper.

DS2500s (especially in the wet) pretty much rust onto the discs leaving uneven deposits. This is noticeable when braking lightly (well, not hard) from higher speeds e.g. 70.

PITA and spoils an otherwise very good pad for the road. Pagid Blacks had no such problems though IIRC didn't have quite as good cold bite.

Mine vibration comes from through the wheel too. AP six pots (CP57....oh, the best ones!!) :) so very unlikely to be a seized caliper.

DS2500s (especially in the wet) pretty much rust onto the discs leaving uneven deposits. This is noticeable when braking lightly (well, not hard) from higher speeds e.g. 70.

PITA and spoils an otherwise very good pad for the road. Pagid Blacks had no such problems though IIRC didn't have quite as good cold bite.

No such thing as a warped disc, it is all most impossible to warp a disc, you do a search on the net and have a good read , as dunx says it will just be deposits from the pads on the discs mate.

I've warped a disc, but it was down to the minimum recommended thickness.....

Non-Subaru.

dunx

I've warped a disc, but it was down to the minimum recommended thickness.....

Non-Subaru.

dunx

Any suggestions on what pads to go for guys?
(fast road and some track use - Ian Godneys refurbed subau 4 pot calipers)
I have always got on well with pagid.
Thanks

I had mintex 1144's on an AP set up, very good :D but if you want the pagid then go for them, not the cheapest but damned good :D

Tony:)

Thanks Tony ..thinking about it I will go for the pagid as it is what I know.
Always had pagid blue (carbon) - but dont know if to go for pagid black(ceramic) ?