which fluid
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which fluid
Any recommendations for brake fluid? Did a track day a bit ago and i think i cooked the fluid off. Do have plans for more track work so what fluid should i use? Primarily a road (every day) car. Odd track day use.
Cheers
Ritchie.
Cheers
Ritchie.
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From: In the Flatlands of Lincolnshire
Hi M8/. I have recently changed the brake fluid in my bugeye for Automec Silicon brake fluid. This is DOT 5 spec and supposidly never needs changing. It is quite expensive at £24.50 per litre from Demon Tweeks can also be got from Automec online. It is somewhat thinner than normal brake fluid but seems ok so far.
Originally Posted by Ritch96
Any recommendations for brake fluid? Did a track day a bit ago and i think i cooked the fluid off. Do have plans for more track work so what fluid should i use? Primarily a road (every day) car. Odd track day use.
Cheers
Ritchie.
Cheers
Ritchie.
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From: Surviving as a soldier of fortune on the Los Angeles underground...
Using AP Racing fluid dot 5.1 from Demon tweeks. IIRC the 5.1 fluids need to be replaced about every 6 months, whereas the dot 4 fluids will usually last between service intervals.
I was also recommended Motul fluid BTW.
I was also recommended Motul fluid BTW.
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From: At the bottom of a glass
Changing calipers soon so this got me thinking....
Did some searching and came up with:-
So looks like 5.1 is the way to go.
Did some searching and came up with:-
DOT 3: This brake fluid has a glycol base with additives. It is clear to amber in color. It is hygroscopic (meaning it absorbs moisture) and has a minimum dry boiling point of 401°F (205°C) minimum and a minimum wet boiling point of 284°F (140°C). It will absorb 1 to 2 percent of water per year depending on climate and operating conditions. It is used in most domestic cars and light trucks in normal driving. It does not require cleaning the system and it can be mixed with DOT 4 and DOT 5.1 without damage to the system. The problem with it is that it absorbs moisture out of the air and thereby reduces its boiling point. It can also damage the paint on a vehicle.
DOT 4: This brake fluid also has a glycol in it but the SAE J1704 specification considers it to be a borate ester base fluid. Typically in the high performance fluids, it also contains other additives. It is clear to amber in color. It is hygroscopic (meaning it absorbs moisture) and has a minimum dry boiling point is 446°F (230°C) and minimum wet boiling point of 311°F (155°C). It is used in many European cars; also for vehicles in high-altitude, towing, or high-speed braking situations, or ABS systems. It does not require cleaning the system and it can be mixed with DOT 3 without damage to the system. The problem with it is that it absorbs moisture out of the air and thereby reducing its boiling point, however it absorbs moisture at a rate slower than DOT 3. It can also damage the paint on a vehicle.
DOT 5: This brake fluid has a silicone base. It is purple in color. It is NOT hygroscopic (meaning it cannot and will not moisture) and has a minimum dry boiling point of 500°F (260°C) and a minimum wet boiling point of 356° (180°C) It is not used in many brake applications, seeing primary duty in weekend, antique, and collector cars that sit for long periods and are never driven far. It does not mix with DOT 3, DOT 4, or DOT 5.1. It will not absorb water and will not damage the paint on a vehicle. It is also compatible with the same rubber formulations as the DOT 3, 4 & 5.1 fluids. The problem with it is that it can easily get air bubbles into the system. The air bubbles are nearly impossible to remove and result in poor system performance and poor pedal feel. Although originally developed in the late 1960's by General Electric specifically for racing, it is unsuitable for racing for a variety of reasons. (Click here for the silicone story) If as little as one drop of water enters the fluid, severe localized corrosion, freezing, or vapor lock may occur. This can happen because water is heavier and not mixable with silicone fluids. It is unsuitable for ABS.
DOT 5.1: This brake fluid is similar to DOT 4 it has a base comprised primarily of Borate Ester. Often in the range of 70 - 80%. To meet specification, it also will contain other additives. It is clear to amber in color. It is hygroscopic (meaning it absorbs moisture) and has a minimum dry boiling point of 500°F (260°C) and a minimum wet boiling point of 356°F (180°C) minimum. It is almost exclusive to Europe, used in high performance cars. It can be mixed with DOT 3 or DOT 4 without damage to the system. It maintains higher boiling point than DOT 3 or DOT 4 fluids due to its even greater borate ester content. It is excellent for severe duty and racing applications. The problem with it is that it costs more than other fluids and there is limited availability in the USA. It also absorbs moisture out of the air and thereby reduces its boiling point. It can also damage the paint on a vehicle.
DOT 4: This brake fluid also has a glycol in it but the SAE J1704 specification considers it to be a borate ester base fluid. Typically in the high performance fluids, it also contains other additives. It is clear to amber in color. It is hygroscopic (meaning it absorbs moisture) and has a minimum dry boiling point is 446°F (230°C) and minimum wet boiling point of 311°F (155°C). It is used in many European cars; also for vehicles in high-altitude, towing, or high-speed braking situations, or ABS systems. It does not require cleaning the system and it can be mixed with DOT 3 without damage to the system. The problem with it is that it absorbs moisture out of the air and thereby reducing its boiling point, however it absorbs moisture at a rate slower than DOT 3. It can also damage the paint on a vehicle.
DOT 5: This brake fluid has a silicone base. It is purple in color. It is NOT hygroscopic (meaning it cannot and will not moisture) and has a minimum dry boiling point of 500°F (260°C) and a minimum wet boiling point of 356° (180°C) It is not used in many brake applications, seeing primary duty in weekend, antique, and collector cars that sit for long periods and are never driven far. It does not mix with DOT 3, DOT 4, or DOT 5.1. It will not absorb water and will not damage the paint on a vehicle. It is also compatible with the same rubber formulations as the DOT 3, 4 & 5.1 fluids. The problem with it is that it can easily get air bubbles into the system. The air bubbles are nearly impossible to remove and result in poor system performance and poor pedal feel. Although originally developed in the late 1960's by General Electric specifically for racing, it is unsuitable for racing for a variety of reasons. (Click here for the silicone story) If as little as one drop of water enters the fluid, severe localized corrosion, freezing, or vapor lock may occur. This can happen because water is heavier and not mixable with silicone fluids. It is unsuitable for ABS.
DOT 5.1: This brake fluid is similar to DOT 4 it has a base comprised primarily of Borate Ester. Often in the range of 70 - 80%. To meet specification, it also will contain other additives. It is clear to amber in color. It is hygroscopic (meaning it absorbs moisture) and has a minimum dry boiling point of 500°F (260°C) and a minimum wet boiling point of 356°F (180°C) minimum. It is almost exclusive to Europe, used in high performance cars. It can be mixed with DOT 3 or DOT 4 without damage to the system. It maintains higher boiling point than DOT 3 or DOT 4 fluids due to its even greater borate ester content. It is excellent for severe duty and racing applications. The problem with it is that it costs more than other fluids and there is limited availability in the USA. It also absorbs moisture out of the air and thereby reduces its boiling point. It can also damage the paint on a vehicle.
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From: north east
be very wary of 5.1 as not all are equal........................
the temp. rating is not the only factor in the DOT rating and in a lot of circumstances soem track/race type fluids may 'only' be dot4, or no rating at all, and yet still far outperform 5.1's..................
alyn
the temp. rating is not the only factor in the DOT rating and in a lot of circumstances soem track/race type fluids may 'only' be dot4, or no rating at all, and yet still far outperform 5.1's..................
alyn
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Originally Posted by stockcar
be very wary of 5.1 as not all are equal........................
the temp. rating is not the only factor in the DOT rating and in a lot of circumstances soem track/race type fluids may 'only' be dot4, or no rating at all, and yet still far outperform 5.1's..................
alyn
the temp. rating is not the only factor in the DOT rating and in a lot of circumstances soem track/race type fluids may 'only' be dot4, or no rating at all, and yet still far outperform 5.1's..................
alyn
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