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.

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7answers
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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 ...
14
votes
2answers
528 views

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?
12
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1answer
121 views

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 ...
11
votes
1answer
125 views

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 ...
10
votes
1answer
61 views

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 ...
9
votes
3answers
7k views

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 ...
7
votes
2answers
308 views

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 ...
7
votes
1answer
52 views

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 ...
6
votes
2answers
216 views

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 ...
5
votes
3answers
4k views

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 ...
5
votes
2answers
393 views

Clutch sticking, wait until engine's warm

I drive a 96 Honda Del sol it's got about 200k on the engine. So lately my clutch hasn't been going into first or neutral when I try to start it. There is often very little resistance in the clutch at ...
5
votes
3answers
12k views

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 ...
5
votes
1answer
90 views

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 ...
4
votes
1answer
84 views

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 ...
4
votes
2answers
1k views

Mixing brands of DOT4 brake fluid

I have changed my DOT3 brake fluid to DOT4 brake fluid. Will it hurt to mix DOT4 fluid with another brand of DOT4 fluid?
4
votes
2answers
167 views

Is it necessary to bleed brakes if the system is never opened?

Just wondering if there is a point to bleeding the brakes if the system is never opened, since it's effectively a closed system. For example, does the chemical change should the fluid reach boiling ...
4
votes
1answer
260 views

Does brake fluid require topping-up as brake pads wear out?

The other day I was watching a video of a guy changing brake pads, and the first thing he suggested was opening the brake fluid container to remove some fluid with a syringe. This is to avoid ...
3
votes
3answers
172 views

Is it possible to tell if brake fluid needs to be flushed just by looking at it?

I've got spongy brake feel. This situation has me wondering if it is at all possible to tell that brake fluid needs changing just by looking at the fluid in the reservoir, similar to how you can tell ...
3
votes
1answer
112 views

Spongy brakes after brake pad swap - moisture or bubbles?

I changed the rear brake pads on my BMW last week, following the steps outlined in this video. Unfortunately the brake pedal now feels spongy. The pedal feel was firm prior to the brake swap, so it ...
3
votes
1answer
105 views

Brake fluid gone, rear brakes out. '99 pathfinder

The other day I started my car and the e-brake light stayed on after releasing it and I figured it was electrical at first. When I started using the brakes I realized I had to push about twice as far ...
3
votes
1answer
59 views

Is vehicle's fluid level monitoring the best way to detect all leaks?

I did an oil change for my friend's car and the mechanic was trying to convince me that it is leaking oil and brake fluid. He suggested that the car needs a costly repair (~$1400). While I don't have ...
3
votes
2answers
235 views

Brake pedal is hard to push even after new brakes

The brake pedal in my 06 Pontiac g6 seems harder to push than normal. Since the issue started, I've had the rear rotors and pads replaced, along with a control arm. For the first 10-15 minutes of city ...
2
votes
1answer
218 views

Could my brake problems be caused by a wrong kind of brake fluid?

The brake light is on in my 2007 Toyota Tacoma 4WD v6. The recurring pattern has been that I would fill up the brake fluid but then it would drop below the minimum mark after just a few days. It ...
2
votes
1answer
30 views

Specifics about changing a brake caliper on 2000 Toyota Camry

I went to change the brake fluid in my 2000 Toyota Camry and when I tried to unscrew the bleeder nipple on a front caliper it broke in half rather than unscrewed. So, I need to replace the caliper ...
2
votes
2answers
6k views

Vaxhall Astra H clutch problem

A couple of months ago I noticed some problems starting with the clutch; the pedal became extremely spongy and the biting point was right down at the bottom, expecially on cold starts first thing in ...
2
votes
1answer
1k views

How to bleed Toyota Tacoma clutch system?

Vehicle: 2007 Toyota Tacoma 4WD v6 6 speed I found this tutorial on pre-bleeding but it is generic (not vehicle specific) and I think there are differences between the cylinder it uses and Tacoma's, ...
2
votes
1answer
262 views

How to avoid having air bubbles in clutch line after cylinder replacement?

I am in the process of replacing the clutch master cylinder on my 2007 v6 Tacoma. When I detached the old one, I tried to minimize the leakage of the brake fluid. Once I put the new part in and add ...
2
votes
1answer
64 views

Can I use DOT 4 brake fluid when DOT 4+ is recommended?

My Chevrolet Lumina SS calls for use of "Heavy Duty Brake Fluid (DOT-4 Plus)". The brake fluid bottle I have readily available is DOT 4; the label claims to be compatible with DOT 4 and DOT 5.1 ...
2
votes
1answer
510 views

Ford Escort - Brake Fluid leak in car

I own a Ford Escort 1992, 1.9l, manual. Recently my default-idle had been really high and so I did some research and figured out that my brake booster probably broke. So I went to the junkyard and got ...
2
votes
1answer
1k views

Brake fluid reservoir level drops fast to minimum but not below

The brake fluid reservoir level drops very fast in my 2007 4WD V6 Toyota Tacoma, probably within 3-5 days of filling it up. The funny thing is, it drops to just below where it says minimum but not ...
1
vote
1answer
175 views

How to clean brake fluid spillage from vehicle floor?

I had a leak out of my clutch master cylinder for quite a long time (until I figured what it was causing it). The floor mat is pretty soaked in brake fluid (and I am replacing it) but there are also ...
1
vote
2answers
56 views

Is it necessary to purge the entire brake circuit if only the front wheels flexible are changed?

The vehicle does not have ABS. It is the typical X configuration.
1
vote
1answer
2k views

Skoda Fabia, flashes handbrake light and beeps 3 times

When I turn heavy or accelerate hard in my Skoda Fabia the handbrake light flashes approximately 5 times and beeps exactly 3 times.