Brake Fluid

What are the Different Types of Brake Fluid?

A hydraulic braking system incorporated into your automobile is a precisely designed or engineered system that demands the right type of brake fluid to function properly. When compared to other vehicle fluids, brake fluid types are not diverse. There are only 5 types of brake fluid available on the market today. Each type of brake fluid serves the same purpose, but the extensive features offered would be different.

In this article, we would discuss each type of brake fluid so that you could pick the best brake fluid for your automobile easily.

Brake Fluid

  • DOT 3
  • DOT 4
  • DOT 5
  • DOT 5.1
  • DOT 2

DOT 3 

This type of brake fluid is amber-colored and also glycol-based. They come with the lowest dry boiling point and a low wet boiling point. Most commonly, a low range of commuter vehicles uses this type of brake fluid as it is comparatively cheap. However, since this type of brake fluid is hygroscopic, the user will have to change the fluid every year to maintain braking efficiency.

  • Boiling point – 401-degree Fahrenheit
  • Degraded boiling point – 284-degree Fahrenheit

DOT 4 –

Majority European car manufacturers use DOT 4 brake fluid in their hydraulic braking system. This type of brake fluid is glycol-based and comes with borate-ester additives that increase the boiling point by reducing the formation of acid due to moisture absorbed. In general, DOT 4 brake fluid costs twice as much as DOT 3 brake fluid.

  • Boiling point – 446-degree Fahrenheit
  • Degraded boiling point – 311-degree Fahrenheit

DOT 5 –

This type of brake fluid is silicone-based and is designed in such a way that it does not absorb water like any other brake fluids. Therefore, it has a high boiling point, distinct purple hue, and cost almost the same as DOT 4 braking fluids. However, this type of braking fluid is not compatible with all types of the hydraulic braking system as it has a drawback of foaming and air bubble that could lead to inefficient braking. Apart from this, since the fluid does not absorb moisture, any sort of fluid that comes in contact with it could corrode it and lead to unfavorable freezing and boiling points.

DOT 5 brake fluids are not commonly used as they lack air and water insolubility. Apart from that, they are best for vehicles that sit in storage for a long time and could be used without any preparation or notice.

  • Dry boiling point – 500-degree Fahrenheit
  • Wet boiling point – 356-degree Fahrenheit

DOT 5.1 –

This type of braking fluid is almost similar to DOT 4 racing fluid, however, this one has different properties and features. DOT 5.1 braking fluid is commonly known to be DOT 4 in terms of boiling point and DOT 5 in terms of chemical makeup. This braking fluid is almost 15 times more expensive than DOT 3, but one of the biggest advantages of this braking fluid is that it could mix with both DOT 3 and DOT 4 braking fluids.

  • Dry boiling point – 500-degree Fahrenheit
  • Wet boiling point – 356-degree Fahrenheit

DOT 2 –

DOT 2 braking fluid is commonly not used in automobiles as they have low wet and dry boiling points. Apart from this, DOT 2 braking fluids are mineral-based and they are less efficient than other braking fluids.

  • Dry boiling point – 374-degree Fahrenheit
  • Wet boiling point – 284-degree Fahrenheit

Brake fluids should always be selected carefully, each model hydraulic braking system is designed to load with a specific type of braking fluid. Check the manufacturer’s instructions and use an appropriate braking fluid only.