Brake Fluid

[normank]

Is there a difference between the high end, high temp brake fluids like:

Castrol SRF

ATE Super Blue

Motul

How often does it need to be changed and/or how can you tell?

[Flash1034]

I hear the castrol SRF is VERY hygroscopic and needs to be replaced often. It is also VERY expensive. Most guys I know, myself included, use Motul 600 or ATE Blue Racing fluid.

Flash

[normank]

I hear the castrol SRF is VERY hygroscopic and needs to be replaced often. It is also VERY expensive. Most guys I know, myself included, use Motul 600 or ATE Blue Racing fluid.

Flash

How often do you change it? Is it a time and/or miles calculation or can you test it. I would also be interested in what you do about oil.

Thanks for your input.

Norman

[Qualified Pole]

Is there a difference between the high end, high temp brake fluids like:

Castrol SRF

ATE Super Blue

Motul

How often does it need to be changed and/or how can you tell?

Sorry, but Flash is mistaken. While SRF *is* very expensive ($75 a liter), it is radically less hygroscopic than ATE. I have no first-hand experience with Motul.

After years of using ATE super blue (and Typ 200--same thing but gold) in 2 996 track cars (one a GT3) and my BMW track and race cars, I got fed up with soft pedals and bleeding brakes. SRF is not a one-bleed-a-season miracle cure, but I have not had to bleed my brakes during a 3-day race or DE weekend since I went to SRF (I used to need to bleed daily with ATE). So far, SRF has lasted 5 to 1 to ATE in volume (waaaay less bleeding), and the time saved alone is worth its cost.

I didn't believe it until I tried it.

[Qualified Pole]

For a couple more data points, here are the Dry/Wet boiling points in degrees Fahrenheit:

Castrol SRF: 590 / 518

Motul 600: 594 / 421

ATE SupBlue: 536 / 396

[Tool Pants]

For a street car you can't go wrong with Ate. It has slightly higher boiling points then the stuff sold by Porsche. I think Porsche says to change it every 2 years. I'm talking about a street car.

http://www.renntech.org/forums/index.php?showtopic=2810

Most of the local owners use Ate, the amber or blue. It is about $10 a liter and you will use about 2/3rds of the can. The amber and blue stuff have the same specs. The blue stuff is just a dye. It has been said that the blue stuff is called "racing" because it is not DOT approved because of the dye. To be DOT approved brake fluid is supposed to be an amber color. From the picture you can see the boiling points for both are the same.

[normank]

After years of using ATE super blue (and Typ 200--same thing but gold) in 2 996 track cars (one a GT3) and my BMW track and race cars, I got fed up with soft pedals and bleeding brakes. SRF is not a one-bleed-a-season miracle cure, but I have not had to bleed my brakes during a 3-day race or DE weekend since I went to SRF (I used to need to bleed daily with ATE). So far, SRF has lasted 5 to 1 to ATE in volume (waaaay less bleeding), and the time saved alone is worth its cost.

I didn't believe it until I tried it.

QP

I'm very new to all this so bear with me. When you say "bleed" do you mean "change" the brake fluid? At the moment, I'm not in a position to do it myself. What's involved and how do you know you need to do it? Thanks for your help.

By the way I had the brake fluid changed to ATE Super Blue after 3 DE's (novice). I ran 1 DE and am now moving to the intermediate group. I'm guessing that I will need to pay more attention to the brake fluid and oil as I progress.

Norman

Edited September 23, 2007 by normank

[Loren]

Flush, bleed, change -- basically all the same.

You put new fluid in the brake fluid reservoir and push out the old fluid at each wheel (and clutch) bleed point.

There is a DIY here.

[Qualified Pole]

QP

I'm very new to all this so bear with me. When you say "bleed" do you mean "change" the brake fluid? At the moment, I'm not in a position to do it myself. What's involved and how do you know you need to do it? Thanks for your help.

By the way I had the brake fluid changed to ATE Super Blue after 3 DE's (novice). I ran 1 DE and am now moving to the intermediate group. I'm guessing that I will need to pay more attention to the brake fluid and oil as I progress.

Norman

Norman, Loren's DIY tells you how to bleed using a power bleeder. But, keep your car serviced and don't worry about brake fluid, tires, etc. until you start outdriving (or in my case, overdriving) your equipment. Presuming you're driving a GT3 or RS around the track, congratulations! Your equipment should be fine until you start overbraking or really get going fast enough that you need to put that much heat into the braking system.

You will know you need to bleed your brakes by your pedal starting to feel soft when you are braking. Don't worry, this is not something you have to be looking for, you will know when it happens. And, it is simply compensated for by [a] pushing harder and then pumping the brake pedal in an extreme situation. That said, learn the line, be smooth and make sure your brakes have been bled within your region's requirements.

Regarding definitions, bleeding as I use it means getting the air and any contaminated fluid out of your calipers and close vicinity. In my vocabulary, flush means replacing as much old fluid for new, as can be done, plus a little extra to make sure you have as much air and water out of your brake and clutch system as possible. BTW, all brake fluid is hygroscopic (it absorbs moisture), and the pedal goes soft because the water boils and becomes vapor and vapor compresses (this is where the soft pedal comes from), whereas liquids do not.

[normank]

QP

I'm very new to all this so bear with me. When you say "bleed" do you mean "change" the brake fluid? At the moment, I'm not in a position to do it myself. What's involved and how do you know you need to do it? Thanks for your help.

By the way I had the brake fluid changed to ATE Super Blue after 3 DE's (novice). I ran 1 DE and am now moving to the intermediate group. I'm guessing that I will need to pay more attention to the brake fluid and oil as I progress.

Norman

Norman, Loren's DIY tells you how to bleed using a power bleeder. But, keep your car serviced and don't worry about brake fluid, tires, etc. until you start outdriving (or in my case, overdriving) your equipment. Presuming you're driving a GT3 or RS around the track, congratulations! Your equipment should be fine until you start overbraking or really get going fast enough that you need to put that much heat into the braking system.

You will know you need to bleed your brakes by your pedal starting to feel soft when you are braking. Don't worry, this is not something you have to be looking for, you will know when it happens. And, it is simply compensated for by [a] pushing harder and then pumping the brake pedal in an extreme situation. That said, learn the line, be smooth and make sure your brakes have been bled within your region's requirements.

Regarding definitions, bleeding as I use it means getting the air and any contaminated fluid out of your calipers and close vicinity. In my vocabulary, flush means replacing as much old fluid for new, as can be done, plus a little extra to make sure you have as much air and water out of your brake and clutch system as possible. BTW, all brake fluid is hygroscopic (it absorbs moisture), and the pedal goes soft because the water boils and becomes vapor and vapor compresses (this is where the soft pedal comes from), whereas liquids do not.

QP

Thanks for painting that clear picture. I suspect you are correct on every point. I spend a good deal of time on the track reminding myself not to over drive, which is a major problem with a GT3. Smooth is fast and stay off the grass (although I have been told grass is a racing surface and makes the car go faster).

Norman

[toadinlaw]

Anyone have experience with RGS610 see www.renugroupllc.com. my mechanic recommends this stuff Dry 610 (f) Wet 421 (f). I have not tried it yet but it sonly 20.00 per 500 ml.