Brake fluid change
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Brake fluid change
I intend to change-out the brake fluid in my corvette. Is it advisable to convert to DOT 5 silicon brake fluid which is incompatible with the original fluid which is DOT 3? Regardless of what fluid I use, how is fluid in the ABS flushed out? Also, although brake fluid is hygroscopic, how does it absorb moisture from the air considering the system is closed?
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Burning Brakes
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I intend to change-out the brake fluid in my corvette. Is it advisable to convert to DOT 5 silicon brake fluid which is incompatible with the original fluid which is DOT 3? Regardless of what fluid I use, how is fluid in the ABS flushed out? Also, although brake fluid is hygroscopic, how does it absorb moisture from the air considering the system is closed?
You can use DOT 4. It is compatible with DOT3.
I use ATE Type 200 DOT4 fluid, but living in the mountains and driving my car hard on back roads, I get my brakes very hot.
This Prestone AS800Y DOT 4 Synthetic is good stuff too:
I use a Motive power bleeder to bleed my brakes. I just did mine this weekend and it makes the job super easy. Just hook it up to your master cyl and a compressor. Put about 5 or 10 psi on it and it will push the fluid through the system. Make sure to keep the master cyl topped off so you don't push any air into the system. Before you start, you can use a syringe to pull the old fluid out and fill it with fresh.
https://www.motiveproducts.com/colle...-3-tab-adapter
Last edited by dmk0210; Jul 6, 2021 at 01:01 PM.
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Ford Super High Performance Dot 3.
Less than $10. a pint at a Ford dealership parts dept.
Good bang for the buck and compatible.
ABS, you need a Tech II to open the system; flush and pedal feel will be okay even without opening the circuit.
Absorption. Over time I'd suppose very small leaks through all the system seals. Flushing every two years is superior maintenance.
Have fun.
Less than $10. a pint at a Ford dealership parts dept.
Good bang for the buck and compatible.
ABS, you need a Tech II to open the system; flush and pedal feel will be okay even without opening the circuit.
Absorption. Over time I'd suppose very small leaks through all the system seals. Flushing every two years is superior maintenance.
Have fun.
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DOT 5 is a no-no its Silicone based and will not mix or work with conventional DOT3 or DOT4 fluids.
DOT 5.1 is good, higher boiling point (wet or dry) than DOT 3 or DOT4. Lower viscosity more stable viscosity (better cold and hot performance, better ABS cycling).
DOT 5.1 is good, higher boiling point (wet or dry) than DOT 3 or DOT4. Lower viscosity more stable viscosity (better cold and hot performance, better ABS cycling).
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I've read-up a little on brake fluid since the post. It seems that DOT 5 is primarily used by the military in enviornments where moisture is a problem. The silicone base is not hygroscopic. It is however, not for use in normal passanger vehicles because it is not compatible with glycol base brake fluid and will cause ABS failure. DOT #3, #4 and #5.1 are all gylcol based and are compatible with one another. #5.1 has a boiling point of 500 degrees but is 3x more expensive than #4 and is about as hygroscopic. All of them have a freezing point of about -40F.
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Burning Brakes
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Even if you are tracking the car, DOT4 is fine for most.
ATE typ 200 has a dry boiling point of 563 degrees, wet boiling point of 388 deg.
https://www.ate-brakes.com/media/232...typ200-web.pdf
Prestone Dot4 has a dry boiling point of 510 deg, wet boiling point of 311 deg (or 325 deg depending on source).
https://www.autoguide.com/best-brake-fluids
Ford Super High Performance Dot 3 has a dry boiling point of 500 deg, wet boiling point of 284 deg.
https://www.motorcraft.com/us/en_us/...ke-fluids.html
ATE typ 200 has a dry boiling point of 563 degrees, wet boiling point of 388 deg.
https://www.ate-brakes.com/media/232...typ200-web.pdf
Prestone Dot4 has a dry boiling point of 510 deg, wet boiling point of 311 deg (or 325 deg depending on source).
https://www.autoguide.com/best-brake-fluids
Ford Super High Performance Dot 3 has a dry boiling point of 500 deg, wet boiling point of 284 deg.
https://www.motorcraft.com/us/en_us/...ke-fluids.html
Last edited by dmk0210; Jul 8, 2021 at 07:10 AM.
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I take it the dealership and have them flush and service the system with clean fluid.
They know what fluid is recommended.
They know what fluid is recommended.
Burning Brakes
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Mainly because GM wants the same fluid in all their cars so the dealer only has to stock one. The clutch was probably shipped to Bowling Green by the supplier already filled and bled hence the DOT4 in that application.