What Color Should Brake Fluid Be – A Complete Instruction

What color should brake fluid be? The information below will give you an insight into brake fluids. We all know that the role of the brake is necessary as it can protect us from obstacles ahead.

However, we may underestimate the importance of brake fluid. It needs to effectively transfer the pressure from the brake lever to the pads so that the brake can stop the spinning wheel.

But what should brake fluid look like? The colors of the fluid will tell you if you are using a suitable product or not.

Do The Brake Fluid Colors Influence The Braking System?

Do The Brake Fluid Colors Influence The Braking System

There are various brake fluids with distinct colors and different ingredients. When people dilute the fluid improperly, the color will change, heat up, boil and catch fire.

Therefore, we must be careful in choosing the right color for a brake system.

If your brake fluid becomes dark, it means the fluid is old and you need to change it. Otherwise, there will be some problems, including increased corrosion, wear on brake components, and causing braking issues.

Is There A Difference Among Colors of Brake Fluid?

Brake fluids have different colors. The main reason for this is their ingredients, making it easy to differentiate various fluids. Brake fluids have various pigments.

The more pigmented a fluid is, the less it can be diluted.

Time also affects the color of brake fluids. Over time, it can become contaminated, and the dirty brake fluid has a darker color. Also, the color may depend on the vehicle fluid container. If it is leaked, the color will change.

What Is the Meaning Of DOT Brake Fluid?

Most people nowadays prefer using DOT fluid. DOT Brake Fluids are created from a poly-glycol base except for the DOT 5 brake fluid.

The manufacturers make the materials using ten ingredients. People classify these substances into four major components with different characteristics and functions.

  • A Modifier – Coupler- The intensity of swelling on the rubber parts depends on it.
  • Inhibitors – It prevents corrosion and oxidation.
  • A Lubricant -They will keep the parts moving smoothly and freely from 20 to 40%.
  • A Solvent Diluent – The viscosity and boiling point rely on these components.

The Department of Transportation names these Brake Fluid DOT. Good brake fluid has to meet the standard of the Society of Automotive Engineers and the Department of Transportation.

There are various DOT colored brake fluids, such as DOT 5, DOT 2, and DOT 3 brake fluids. The difference among these DOT brakes fluid is the boiling point, which is the temperature at which brake fluid starts boiling and vaporizing.

What Color Should Brake Fluid Be?

What Color Should Brake Fluid Be

There are five common DOT brake fluids that people usually use. They have different colors and physical traits.

Some would withstand very high temperatures, while others have corrosion protection. To ensure you choose the right one, continue reading to learn about their features.

DOT 3 

What Is DOT 3 Fluid?

DOT3 brake fluid is fully synthetic with a non-silicone and mineral base. The mix of alcohol and glycerin with polyethylene glycol ether technology allows it to be used in clutch and brake. 

One of the main features of the fluid is high boiling points, making its performance safe and consistent. DOT 3 brake fluids can withstand cold and high temperatures up to 250°C.

Another advantage of the DOT 3 brake fluid is the minimal rubber component swell. It will prevent the fluid from leaking. You don’t need to worry about the component lifespan as this material has great corrosion protection.

What Color Is Brake Fluid DOT 3?

DOT3 is one of the oldest types of brake fluid. So people usually use them as old means of transportation.

The color of fresh brake fluid is blue. However, it turns darker blue when you use it or leave it in your storage for a long time.

The fluid naturally absorbs moisture and will tend to absorb the water from the air. Therefore, when you open the bottle, ensure to reseal it after usage.

Otherwise, this clean fluid may become darker in color, getting contaminated and less effective.

Some notices you should remember are wearing protective gear and avoiding direct skin contact. Some people would mix it with other DOT fluids, and the color may change. But you shouldn’t mix with Mineral or Silicone DOT 5.


What Is DOT 4 Fluid? 

The selling point of DOT 4 fluid is the glycol ether and borate esters. The combination of the two materials heightens the product’s performance.

The presence of borate ester allows it to have higher dry and wet boiling points, enabling it to be more stable than DOT 3 brake fluid. As the set standard, the minimum dry and wet boiling points are 155°C and 230° accordingly.

The recommended time for fluid usage is two years, which will ensure great brake system performance and user safety.

If you don’t change this DOT 4 fluid as the time given, master cylinder rubber parts or wheel cylinders will begin corroding, damaging the braking system.

What Is The Color Of Brake Fluid DOT 4?

The DOT 4 fluid features a yellowish color. Its purpose is to replace the DOT 3 with better-wet strength and water resistance.

However, once it absorbs water, the color will turn to deep darker yellow. The boiling point falls faster than DOT 3, and it destroys metal quicker.

People can mix DOT 4 with DOT 3 and DOT 5.1 without causing any damage. The color will differ based on the ratio.

DOT 5 

What Is DOT 5 Fluid?

This DOT 5 is a silicon fluid that people usually use in modern cars. Because it has a high boiling point and a dry boiling temperature of up to 356 degrees Celsius, the fluid is a bit expensive.

This color brake fluid type is suitable for modern cars as newly-released brake rotors are small and thin to disperse heat. This silicon brake liquid matches the criteria as it can withstand high temperatures.

The DOT 5 is like a weather barrier that does not absorb moisture. Therefore, it can be seen as a brake system protector. Even when they leak, they resist rust formation and stay longer than other products.

Color of DOT 5 Fluid 

DOT 5 brake fluid has a purple color. Thanks to its high-temperature tolerance and water resistance, the color will slightly change after using or being exposed to the air over time.

However, after a long time, the color of your brake fluid still darkens. Brown or black colors are the key indicators to change your brake fluid.

DOT 5.1 

What Is DOT 5.1 Fluid?

Some people regard this type of brake fluid as a modification of DOT 5. It is silicone-based with a combination of polyethylene glycol ether and borate ester.

Its characteristics are superior to other brakes, including some features like higher dry and wet boiling temperatures.

The dry boiling temperature can go up to 275 Degrees Celsius. One main function is that it can mix with other glycol-based brake fluids, such as DOT 3 and DOT 4, but not DOT 5. This matching can make an upgrade for these DOTs.

One downside is that the fluid absorbs water, eats paints, and is more expensive than DOT 3 and Dot 4.

Color Brake Fluid DOT 5.1 

The DOT 5.1 is yellow, but unlike the DOT 4, its yellow color features a darker shade. It is like amber. Again, the color will still change after a time of usage.

DOT 6  

This DOT type is one version of new advanced brake fluids. With a high boiling point of 320 deg C and low viscosity, you can utilize DOT 6 Brake fluid in the types of motorsport brakes under extreme heat.

As it is NON-hygroscopic, there will be less corrosion and less moisture contamination. The brake fluid of DOT 6 is a similar shade of purple as DOT 5.

However, with better corrosion resistance effects, the color of fresh brake fluid will slowly change.

What Color Should My Brake Fluid Be When It Needs Replacing?

The color of brake fluid is more useful than you may think. Just look at the brake fluid’s appearance, and you will notice some signs of its quality.

If the color is darkened but retains transparency, it can most likely be usable. Some factors change the color, such as moisture saturation, additives, and base development.

It is a good sign when the transparency has not been lost and there are no visible foreign inclusions.

However, when the brake fluid loses its transparency and there is the presence of dispersed inclusions, it is time to change the fluid.

Even if you use a brake fluid tester and the results are still normal, you should consider replacing the liquid. The appearance of inclusions means the wear of the additives.

What Color Is Brake Fluid Supposed To Be When It Leaks?

When the brake fluid leak outside, the color will turn from clear to a bit yellow and darker with time. Some people may confuse motor engine oil with brake fluid, which has a more silky texture.

Thus, if the silky texture liquid leaks from vehicles, it will likely be brake leaks. The reasons can be a faulty ABS unit, loose bleeder valves, or worn-out brake pads.


The article already gave you the answer for what color should brake fluid be. Various brake fluids will have different colors and can also change due to the outside environment and time.

You’d better check the color of the brake fluid regularly to ensure it can still be usable. Otherwise, replace it regularly or when you see some signs to ensure users’ safety.

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