If im driving F**king hard for ten minutes my brake pedal soon hits the floor all of a sudden but if I pump it, it comes back. If I leave the car for a little to cool down they work again. IT IS NOT BRAKE FADE. I think it's fluid related. I have cheapo peugeot fluid. Could it be boiling or something? Would dot 5:1 solve the problem? No leaking or anything... Any help appreciated. Thanks

Ross

Sounds like brake fade if it's after aggressive driving (Fluid Boiling) unless it is your master cylinder seals failing ,but pumping up the brakes doesn't usually work,

I would recommend a brake fliud change with some vag spec brake fluid .

Most main dealers would charge around £47 + vat for a brake fluid change

Edited 24 May, 201115 yr by VAG123

Yep, it will be the fluid. Get some decent 5.1 in

Thanks guys

ATE super blue/gold.....job done

I wouldn't recommend 5.1 personally. It's a bit too good at absorbing water really, for road use - and will mean you'll need to change it more often.

What I would recommend is Motul RBF 600 or Tarox RoadRace. Both are high performance DOT 4 fluids, exceeding DOT 5.1 and DOT 3 standards.

RBF600 for me. Use it in the track car and after some /very/ heavy sessions on Brembo/Porsche calipers on 312mm discs, they're perfectly fine.

ive got the tarox road/race dot4 stuff does the job for me, awesome gti sell it on there site

RBF600 for me. Use it in the track car and after some /very/ heavy sessions on Brembo/Porsche calipers on 312mm discs, they're perfectly fine.

Another vote for RBF-600. I can't get mine to cook what-so-ever...

And boiling fluid is brake fade, is it not?

I didnt think it was, since brake fade can be improved on standard kit by using decent pads & discs

Matt

I also use RBF600 with my brembo setup and can push it hard on track. I do find though even with that stuff I still (eventually) get brake issues and have to come in to the pit to let them cool down.

How many litres in a Fabia brake setup?

Might try the Motul stuff......

I didnt think it was, since brake fade can be improved on standard kit by using decent pads & discs

Matt

still brake fade though

Castrol SRF for me.

Info on brake fade(s) http://briskoda.net/forums/topic/1843-brakes-brake-fade-causes-and-cures/

Fluid fade

Fluid fade is caused by the boiling of the brake fluid in the calipers. This produces bubbles in the brake system. Since bubbles are compressible, this makes for a soft spongy pedal. In worse cases, the pedal can plunge to the floor with very little slowing! Fluid fade can be avoided by running a high grade racing type brake fluid and/or frequent changes of brake fluid. Also if you change the pads before they get super thin, the remaining friction material will help insulate the calipers from the heat. Some people have had some success with having swaintech spray thermal barrier coating on the backing plate of the pads to help isolate the heat but I have never tried this.

Fluid fade usually has a gradual onset.

Reducing fluid fade

Fluid fade is caused by boiling of the hydraulic fluid in the brake system usually in the calipers and even sometimes the lines under hard use. This localized boiling allows bubbles to form in the brake�s hydraulic system. Since air bubbles are compressible, the end result is a long and mushy brake pedal. In extreme conditions the pedal will go all the way to the floor without much retardation in your speed!

Brake fluid is hydroscopic which means it has an affinity to water and absorbs water from the air. When brake fluid absorbs water it�s boiling point drops rapidly. That why it is important to use only very fresh brake fluid, preferably from a recently opened bottle where the factory seal has just been broken. When bleeding brakes, keep the bottle capped except when you are poring the fluid out. It is also a good practice to keep the cap of the master cylinder reservoir on, but only loosely screwed about � turn while you are bleeding, as the brake fluid pulls in the humidity from the air thus you want to minimize its exposure to the air.

If faced with fluid fade you can sometimes save your ass by rapidly pumping the brake pedal- That was me on track!. This sometimes builds up enough pressure for you to stop or slow enough to avoid disaster. A better way to deal with this is to properly prepare and maintain your vehicle to avoid fluid fade.

didnt you say yourve lost your reservior cap a couple of times? that wouldnt have been good for the fluid, you know when was it changed last?

Another vote for RBF-600. I can't get mine to cook what-so-ever...

And boiling fluid is brake fade, is it not?

Brake fade is the term generally used for when you overheat the discs and/or pads

didnt you say yourve lost your reservior cap a couple of times? that wouldnt have been good for the fluid, you know when was it changed last?

Lost?! Well if it's been missing for any length of time then it's fair to assume that the current fluid has absorbed a fair amount of water in that time. If you bare in mind that opened bottles of brake fluid should be used immediately. Much more than an hour without it being used and an open bottle will start to degrade.

Brake fade is the term generally used for when you overheat the discs and/or pads

But that's hard to distinguish from brake fluid that's passed its maximum capable temperature. And you're in fact more likely for this to happen before the pad/disc combo starts to give up the fight....