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Seems my brake fluid is contaminated causing my brakes to squeak harshly.

Suggestions for best brake fluid and where to obtain same from welcomed. Oh, yeah price is not a limiting factor. Only the best for my old girl.

Cheers
Novice1

Castrol SRF or Motul 600(?) be prepared for sticker shock...

Elf

I've tried Motul RBF600 and it was pretty good. Been though a few track days with that and no big problems. $25 per 0.5L bottle, which isn't too bad imo.

Right now I'm running Quadriga GS610, which cost twice as much as the RBF600 and to be honest, I couldn't tell a big difference. 2 track days with the stuff and still brakes hard, although I did notice it felt a big spongy near the end of the day. The GS610 has a higher boiling point than the RBF600, but then I'm still running on stock rubber lines .

Bang for bucks, RBF600. The best? GS610 or Castrol SRF. GS610 cost me a $45/0.5L while the SRF cost around $130/1L .

Just use a DOT 4 or 5.1 fluid, DOT 3,4 and 5.1 are mineral based and will mix ok if your doing a flush.

Dot 5.0 is silicone and will eat out your brake seals unless your system works with it - it won't however absorb water but any condensation will collect and corrode the space it occupies.

HI:
I, went with a Dot 4 high quality oil.

Found out the real cause of the squeaking was a worn rubbers on the caliper, allowing you to move the caliper by hand, when it should be rock solid.

Cheers
Ron

Slugoid wrote:Bang for bucks, RBF600. The best? GS610 or Castrol SRF. GS610 cost me a $45/0.5L while the SRF cost around $130/1L .

where do you guys go to get your brake fluid

i went to supercheap and all they had was 0.5L for $10 was the max i saw on the shelf

they had Castrol and a few different brands

I never had a problem with DOT3 and just regular bleeding...

AZNTieN wrote:

Slugoid wrote:Bang for bucks, RBF600. The best? GS610 or Castrol SRF. GS610 cost me a $45/0.5L while the SRF cost around $130/1L .

where do you guys go to get your brake fluid

i went to supercheap and all they had was 0.5L for $10 was the max i saw on the shelf

they had Castrol and a few different brands

Try going to brake shops, tuning/motorsport shops or even bike shops for good brake fluid. Autobarn also stock a lot of Motul stuff like the RBF600 and other oils.

Boiling point is the big difference between the standards, especially over the life of the fluid. The higher the boiling point and resistance to absorbed water the higher the price.

- fresh DOT 3 boils at 205 deg C

- fresh DOT 4 boils at 230, but the boiling point is less affected by absorbed water

- DOT 5 is designed primarily for non-corrosive properties on show cars. It's rubbish for real cars. Water condenses in it forming puddles which boil at low temp and rust out brake systems

- fresh DOT 5.1 boils at 260, but is least affected by absorbed water and is most friendly to brake system rubbers

- fresh Race boils at 320 (?) and costs heaps.

(edited for correct values)

and here's a more educated version than mine
http://www.advancepetro.com/differentbrakefluid.htm

I've had my rotors over 630C (my third thermographic marking is gone on my DBA4000's) and I still didn't boil RFB600. I had it in my car over a year and I never had it bubble or had my pedal reach the floor. RBF600 is pretty awesome for a track car. Atleast it has been for me...and I melted hawk hp+ and my DS3000's have been on fire...twice. I used to be mine for $25 a bottle at a Motorcycle store. I know autobahn has it on the shelf as well.

If your not on the track though a dot 4.1/5.1 should suit you fine and will last an awful lot longer than race fluid.....just make sure you flush out the old fluid well to reduce contamination.

Novice1 wrote:Seems my brake fluid is contaminated causing my brakes to squeak harshly.

I don't understand the correlation between fluid quality and squeaking noise.

Novice1 wrote:HI:
I, went with a Dot 4 high quality oil.

Found out the real cause of the squeaking was a worn rubbers on the caliper, allowing you to move the caliper by hand, when it should be rock solid.

Cheers
Ron

Ron, I still think that you may have missed the point about squeaking brakes. Perished rubber boots around the calliper pins will have no effect on brake squeak. The boots are there to contain the grease that allows the pins to remain corrosion free and to slide easily in their operation. the calliper if free floating, that's why you can move it by hand.
Normally the main reason for brake squeak is that the pads haven’t been bedded properly.
Go out and do a series of three HARD stops from 80 – 100 kph and see if that fixes your problem.