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86tuning · 05-17-2008, 09:33 PM

For the most part, regular DOT3 will work fine fine fine for your application.

On a track car (read: racetrack speeds and excessive brake usage and temperatures) you could benefit from a higher temp brake fluid. DOT4 or any of the Super DOT4 brake fluids will work fine. The creme de la creme of super DOT4 fluids is Motul RBF600 which stands for racing brake fluid, 600F boiling point.

On my track car (modified ae86 corolla) I use either RBF600 or DOT5.1 which are both compatible with regular DOT3 and DOT4.

On my truck, I use Toyota DOT3 which is more than sufficient, considering that most of the time the brakes are being used it's going 2mph. Sometimes when I'm driving on the freeway I'll be doing 55mph and a few moderate stops don't even come close to taxing the DOT3 brake fluid boiling point.

The real skinny with brake fluid is that the moisture capacity of a brake fluid effectively decreases with temperature rating increase. So for the most part a DOT4 fluid will hold less moisture than a DOT3. This is not a good thing. On a racecar, it's not a big deal, we do brake maintenance before and after (and sometimes during!) a track session. On a trail rig, you're not likely to do brake maintenance more than once or twice a year.

I would suggest you stick with a regular DOT3 fluid (Toyota fluid works fine) and do a suck n fill of the reservoir once a year. Just get a dollar store turkey baster, and LABEL it BRAKE FLUID so that it doesn't get used for anything else.

As long as the fluid is clean and light yellow, it will work fine. Murky fluids should be flushed out.

Be aware that a neglected system with dark brown or black brake fluid may need more than a simple flush. You may need to overhaul the calipers to get rid of the corrosion inside. And your brake master can actually fail during the bleeding process (but if it does then it was mostly dead anyways).

Now if you're still set on changing brake fluids, you can use any of the following:

DOT3
DOT4
Super DOT4
DOT4 Racing
DOT5.1

The only fluid you absolutely cannot use is DOT5 which is silicone fluid and is NOT compatible with regular brake fluid.

Hope that answers some of your questions.

Cheers!

05-17-2008, 09:33 PM	#4 (permalink)
86tuning Registered User Join Date: Jul 2007 Location: Vancouver, BC Posts: 418	For the most part, regular DOT3 will work fine fine fine for your application. On a track car (read: racetrack speeds and excessive brake usage and temperatures) you could benefit from a higher temp brake fluid. DOT4 or any of the Super DOT4 brake fluids will work fine. The creme de la creme of super DOT4 fluids is Motul RBF600 which stands for racing brake fluid, 600F boiling point. On my track car (modified ae86 corolla) I use either RBF600 or DOT5.1 which are both compatible with regular DOT3 and DOT4. On my truck, I use Toyota DOT3 which is more than sufficient, considering that most of the time the brakes are being used it's going 2mph. Sometimes when I'm driving on the freeway I'll be doing 55mph and a few moderate stops don't even come close to taxing the DOT3 brake fluid boiling point. The real skinny with brake fluid is that the moisture capacity of a brake fluid effectively decreases with temperature rating increase. So for the most part a DOT4 fluid will hold less moisture than a DOT3. This is not a good thing. On a racecar, it's not a big deal, we do brake maintenance before and after (and sometimes during!) a track session. On a trail rig, you're not likely to do brake maintenance more than once or twice a year. I would suggest you stick with a regular DOT3 fluid (Toyota fluid works fine) and do a suck n fill of the reservoir once a year. Just get a dollar store turkey baster, and LABEL it BRAKE FLUID so that it doesn't get used for anything else. As long as the fluid is clean and light yellow, it will work fine. Murky fluids should be flushed out. Be aware that a neglected system with dark brown or black brake fluid may need more than a simple flush. You may need to overhaul the calipers to get rid of the corrosion inside. And your brake master can actually fail during the bleeding process (but if it does then it was mostly dead anyways). Now if you're still set on changing brake fluids, you can use any of the following: DOT3 DOT4 Super DOT4 DOT4 Racing DOT5.1 The only fluid you absolutely cannot use is DOT5 which is silicone fluid and is NOT compatible with regular brake fluid. Hope that answers some of your questions. Cheers! __________________ - Brian Last edited by 86tuning : 05-17-2008 at 09:44 PM.