i use ate super blue racing fluid, and alternate with valvolene yellow high performance every other year. both meet/exceed ferrari's spec. for pre-1989 models. you might also want to do a search for other opinions.
???? Can you really tell the difference between one brake fluid and the other? Shows my ignorance. I thought it was just oil, and that since liquids are not supposed to be compressible, they are all the same? Another lesson learned...
The primary differences in brake fluids is the "wet boiling point". You are correct, in that for the most part, fluids do not compress. Do any of these fluids feel any different "on the street", under normal conditions: No However, on the track...or under extreme braking conditions, there will be less fade, due to the (lack of) the brake fluid boiling, with a "race-type fluid.
You just need to pay close attention to the grade of fluid. i.e whether its DOT 3,4,5 or 5.1 The odd one out is the DOT 5 - that is silicone based & to be avoided generally. It can not be mixed with any other grade of fluid so although it could be used in the system, you would need to drain the whole system down & really clean/flush it out in order to make the switch. DOT 4 is what's used in 90+% of cars. I use Lockheed DOT 5.1 in my 328 & that has a higher boiling point than DOT 4 but is otherwise basically compatible.
Do the fluid every year, or more often if you track it. Brake fluid is hydroscopic/hygroscopic, which means that it will very readily absorm moisture from the air. Even a tiny amount of moisture will dramatically lower the boiling point of the fluid. Additionally, frequent bleeding really helps avoid rusting iron calipers and costly rebuilds. I use Castrol LMA - inexpensive, readily available and in my over built system, quite adequate. hth, chris
DOT 5 (synthetic) fluid should be used only in systems originally designed for DOT 5. Why? The seals in the calipers and the MC are specific to DOT 3/4 or 5 (non-syn v. syn). So it's not a matter of just changing the fluid if introducing DOT 5 - you need to address the seals as well. DOT 5 generally has a higher boiling point but can give a slightly softer pedal v. DOT 3/4. Higher reco the Ate super blue - great stuff.
Any brand should be OK. I use DOT 4. Most cars use DOT 3. Really either is fine for street use. Annual changes are a good idea, especially if you want your brake system to last a long, long time. I used to track 328's a fair amount. The skinny tires keeps the car from ever being a big stopper, but I never ran it out of brakes or boiled the fluid. I think they get about as much as you can out of the stock tires sizes in terms of braking power. Dave
ate racing blue ( together with the EBC yellowstuf = really awesome deceleration and never any fading due to pads or boiling fluid)
All the racing fluids are DOT 4 and are the highest boiling point fluids available. DOT 5.1 was formulated for some ABS systems and is lower viscosity for those systems. The spec really has nothing to do with boiling point. Actually one of the highest boiling point fluids available is Ford Heavy Duty Truck DOT3 fluid but its wet boiling point is too low to be considered a DOT 4. DOT5 silicone fluid is quite compressable and gets more and more compressable as it gets hot. It is why the TUV rejected its use in road cars.
I'm not really interested in getting into a debate on this old issue yet again, but note that I've had silicone DOT 5 exclusively in my 308 for about 5 years now, and regularly do track days at the Mid-Ohio Indy car road course. My brakes get so hot at the end of the lap sessions (120 mph straightaway speed hauled down HARD to a 60 mph 90 degree right turn is the most severe braking point on the track) that you can smell them from the cockpit. The brake pedal remains rock hard firm and does not get soft with hard hot use, much harder use than any street car could ever see. Cheers - DM
Does not change the fact that it is garbage brake fluid, it was never accepted for use in Germany by the German government , it increases your chance of brake failure due to water contamination, increases your chance of brake component damage due to rust and has been rejected by most of the automotive industry for those reasons. But if you are happy, by all means go ahead and use it.
Then maybe you'd care to mention some of the (negligible) compression factors (bulk modulus) of selected liquids....
Actually, all liquids are compressible to some degree. It's just so small for most liquids that we neglect it. Sort of like the ideal gas law. No gas is truly ideal, but the equation works good enough for most calculations. Thus, thermodynamics is about approximations. We never truly calculate any thermodynamic properties with 100% accuracy. But then, your average physics nerd will say that about almost any discipline, which I guess in theory is true also. At least it's not quantum mechanics...then you're just dealing with probabilities. Think of all the arguments that kind of uncertainty would cause here on FChat.
Sorry to disappoint you, but I'm not going to rise up to snap at your bait. Yes, I AM quite happy with DOT 5, and will continue to use it exclusively in all of my hobby cars. My first hand experience speaks for itself. Done and out - DM
The DOT 5 generally does have quite a high boiling point, so, this is certainly helpful for track days. Other folks will have soft brakes (boiling in the calipers) and DOT 5 folks will often be fine. The incremental compressability of DOT isn't a big deal, it's not like the pedal goes to the floor. In a side-by-side comparison most folks wouldn't even notice. It's more apparent with stainless braided brake hoses. That said, DOT 5 does tend to soak up more H2O than 3/4 - just means you need to flush your brake lines more frequently than once every five years!
