Fluid used in the brake system to transfer pedal pressure to the caliper to stop or slow a vehicle. Commonly used types of brake fluid include DOT 3, DOT 4, DOT 5, and DOT 5.1. A higher "DOT" number indicates a higher boiling point of the fluid.
Questions tagged [brake-fluid]
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what is the difference between DOT3 and DOT4 brake fluids?
What is the difference between DOT3 and DOT4 brake fluids?
What could possibly go wrong if I use a (4 times cheaper) DOT3 brake fluid instead of the DOT4 which manufacturer recommends (but allows adding "some" DOT3 occasionally)?
What will happen if…
ria
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Cleaning brake fluid (general tips)
There are some other threads on other websites about cleaning up brake fluid. But I just wanted to get a more organized, concise answer here on SE.
Wanted to confirm that cleaning up brake fluid just requires water and the same detergent you would…
CarlGammaSagan
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Brake flush vs. Replacing the brake fluid
Is a brake flush the exact same thing as replacing the brake fluid?
Or is there a difference?
Amazon Dies In Darkness
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Brake fluid doesn't move in the master cylinder container
I have done a clutch bleed on my Toyota Corolla e120 2006 because I had some difficulties shifting out of 1st gear, I bled it through the slave cylinder and I noticed the fluid was dark black, I was checking the fluid level of course, after clear…
MDrazor
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Using DOT4+ in clutch/brakes when DOT3 is recommended?
Looking at Wikipedia's DOT 3 page, it looks like it's been effectively superseded by DOT 4 fluid, but it's still sold and is still recommended on many forums. This question has an answer saying DOT 4 can be used in DOT 3 systems, but DOT 5 can't.
If…
wjl
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Mixing DOT 4 with DOT 4 synthetic
I couldn't see an existing question about this but please link to it if you know of one ...
I should point out I'm English and the products described are bought in the UK, in case it makes a difference.
The car in question is a 1971 Morris…
user2808054
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My brake fluid all left on short notice. What gives?
During the very cold weather (here in Ohio) recently, I noticed the brakes on my 2000 Chevy Malibu were a little soft, and made a mental note to attend to them promptly.
Then, over the course of 24 hours or so, they went from "a little soft" to "I…
RevKev
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Are resistance/capacitance based brake fluid testers reliable?
I would like to test my brake fluid to see whether it needs replacing rather than spend the time and money on it unnecessarily. I've seen inexpensive brake fluid testers on the market which work on the basis of detecting water percentage based on…
GdD
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Brake fade and spongy brakes at high speeds
I was driving my girlfriends Ford Fiesta last week and it started to experience brake fade.
It always happened after driving the car at higher speeds over 100kmh (60 MPH). The brake pedal became spongy and there was a diminished braking effect. I…
Bogdan Petrica
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How can I dispose of the waste products I get from working on my car more effectively?
I have some real challenges disposing of various fluids and consumable objects from working on vehicles at home in my small workshop.
Some of the more common things that I want to be able to dispose of properly include:
Car Batteries
Brake…
DucatiKiller
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What actually happens when there is no brake fluid in the brake fluid reservoir?
I was curious, given that fact that a lack of engine oil can completely destroy your engine, can a lack of brake fluid completely destroy your brakes? I can imagine how that could be even worst than a broken engine for safety reasons.
*What exactly…
Max Goodridge
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What are all the different types of fluid in a car and a short summary of their use?
A fluid is defined as anything that flows, hence for our purposes a gas or a liquid. I know that there is fuel, engine oil, engine coolant and brake fluid. Also air is normally taken in through a grill on the front of the car.
Are there any other…
Max Goodridge
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What is the difference between DOT4 and DOT5 brake fluid?
I've been going to a lot of muscle car websites the last few days and have seen quite a few recommendations to switch over a brake system from DOT4 to DOT5.
The work that's required seems to revolve around various seals and rubber components within…
DucatiKiller
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How do disk brake pistons retract?
If drum brakes consist of a several springs inside and outside the fluid cylinder to retract the brake shoes after braking, how disk brakes piston, that dont have any springs, can retract alone without any force pulling it back,can vacuum only pull…
user3407319
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Impacts of Overfilling Master Cylinder
When I took a look under the hood of a friend's car, I noticed that the level of brake fluid in master cylinder was slightly above the MAX line. Not by that much, but clearly noticeable. I'll probably remove for her just because MAX means MAX, but…
AA040371
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