What color does brake fluid have?

The role of the brakes is to prevent the wheels from spinning and hence stopping effectively. The brake system will need some fluid to work, and you’ll need to know what color that fluid is for the type of car you’re driving. Here are all of the common colors found in brake fluid:

  • Yellow
  • Amber
  • Blue
  • Brown
  • Purple 
  • Black

Does the brake fluid color influence the braking system?

If the fluid isn’t diluted properly in the brake system, it will boil, heat up, or even catch fire. That is why we must always use the right color for a brake system to prevent this and in this article, you’ll read about all of them.

Is there a difference among brake fluid colors?

One important point is that some fluids have pigment to give them different colors and to make it easier to see from afar. The more pigmented a fluid is, the less it can be diluted; however, if the pigment is used correctly they can provide coloration to other fluids so they provide different shades of gray-green. No law states that you must use only one color.

Which produces a quicker reaction time?

Some brake fluids contain a chemical additive to improve their performance so they react faster on the brake pad, and this is the main reason why each fluid is used by car manufacturers. The resulting change in the brake pads’ coefficient of friction directly relates to braking effectiveness and subsequent stopping force.

This means that cars work better on some types of brakes, for example, red brakes are better than yellow ones. That’s why some cars are using red or black at the rear axle while the front axle uses yellow hoses.

What color does DOT 3 brake fluid have?

DOT 3 brake fluid is the oldest type of brake fluid and it has a blue color when it is new. This is the type of brake fluid usually found in very old vehicles. 

What color does DOT 4 brake fluid have?

DOT 4 brake fluid is yellowish in color. This type of brake was meant to replace the old-fashioned bluish-colored DOT 3 type. It has better water resistance and wet strength than DOT 3 but it also corrodes metal much faster and doesn’t do well with high temperatures either.

What color does DOT 5 brake fluid have?

DOT 5 brake fluid is purple in color and has a high-temperature threshold combined with good water tolerance, which makes it the perfect choice for heavy vehicles that are usually exposed to hot temperatures while driving on highways.

What color does DOT 5.1 brake fluid have?

DOT 5.1 brake fluid is also yellow but has a darker shade (like amber). as a higher boiling point than DOT 4. It was meant to be a replacement for DOT 3 and 4, and it is used in most current vehicles. It is compatible with both ABS and non-ABS systems.

What color does DOT 6 brake fluid have?

DOT 6 brake fluid has a similar shade of purple as DOT 5 but it has better chemical stability at high temperatures. It is used in heavy trucks with ABS systems, which are exposed to extreme heat while driving on highways.

What color does brake fluid have when it needs to be replaced?

Brake fluid usually starts to become darker over time and this is a sign that it needs to be changed.

There are several signs that, without special devices, tell you that the brake fluid is aging and losing its working properties.

Darkening without loss of transparency. A similar color change is associated with the development of the base and additives, as well as with moisture saturation. If the liquid has just darkened but has not lost some transparency, and there are no visible foreign inclusions in its volume, most likely it can still be used. 

It will be possible to find out more precisely only after checking with a special device: a brake fluid tester, which will determine the percentage of water.

Loss of transparency and the appearance of finely dispersed inclusions and dissimilar sediments in the volume. This is a clear sign that the brake fluid has run out to the limit and will have to be changed. 

Even if the tester shows that the moisture is within the normal range, such a liquid must be replaced. Otherwise, problems may appear in the system, since a dark color and dissimilar inclusions indicate wear of the additives.

Even if the color of the brake fluid still seems normal, but its service life has exceeded 3 years for glycolic bases and 5 years for silicone bases, it is necessary to replace it in any case. During this period, even the highest quality options are saturated with moisture and lose their lubricating and protective properties.

Final thoughts

In conclusion, you should be using the right DOT brake fluid for your car, just search for it in your user manual. When choosing it, you should also be careful what you choose, there are some ghost brands that make a lot of low-quality fluids that can harm your braking system.

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