Top 5: Whats The Best Brake Fluid?


Brake Fluid is easily one of the most neglected fluids in most vehicles around the world. Manufacturers recommend that you change your brake fluid every 3 years. The Brake Fluid posses life saving qualities yet people often check everything except the brake fluid.

Best Brake Fluid (Full Brake Fluid Reviews Below)

1.Motul RBF600 Brake FluidDOT 4Check Price
2.Castrol DOT 4 Brake FluidDOT 4Check Price
3.Prestone AS400 DOT 3 Synthetic Brake FluidDOT 3Check Price
4.HI-TEMP 570 Brake FluidDOT 3Check Price


In order to help understand the importance  and to find the best brake fluid we will learn about the chemical properties and what is the purpose of brake fluid.

All Brake fluid are synthetic hydraulic fluid that helps apply pressure to the brake components.

Hydraulic fluids are the mediums used to transfer power through out hydraulic components. Hydraulic fluids are known for transferring force into pressure which is how your foot applying pressure to your brakes stops your vehicle.

This is important because new brake fluid is incompressible, which helps apply quality pressure to the brake mechanism.

This is especially important for:

Those who commute long distances in warm weather. When brake fluid is overheated it puts your brake mechanism at risk. Once the brake fluid begins boiling the fluid turns into a gas and makes the gas compressible. Leaving your brakes very soft and will lead to “cadence braking”.

Cadence braking is also referred to as stutter braking, meaning repeatedly pressing the brake to prevent the brakes from locking up.

Most modern vehicles have anti-lock brakes or “ABS” if there is no pressure in the brake lines this system will not provide to much assistance. There are a few braking techniques here.

You may also be interested in: How to Change Brake Pads and Rotors

Brake Fluid Types:

So as you may or may not notice there are 4 different types of brake fluids.

Fluid Dry ERBP (°F)Wet ERBP (°F)Viscosity LimitChemical
Fluid Dry ERBP (°F)Wet ERBP (°F)Viscosity LimitChemical
Grade @ 0.0% H2O@ 3.7% H2O(Cp @-40°F) Composition
DOT 34012841500 mm2/sGlycol Ether Based
DOT 44463111800 mm2/sGlycol Ether / Borate Ester
DOT 5 (SSBF) 500356900 mm2/sSilicone Based
DOT 5.1500356900 mm2/sBorate Ester/ Glycol Ether

Source: USDOT

* DOT refers to the Department of Transportation and the numbers refer to the different viscosity limit brake fluid is made of.

Viscosity Limit

The brake fluid grade comes from the different temperatures that the fluid maintains while its stable and the corrosion characteristics. There are more characteristics taken into consideration but we are going to just focus on those two.

Viscosity is important to those that have ABS systems because the pressure and volume of fluid is not transferred. This means manufacturer’s suggested viscosity is important to take into consideration.


Is one of two brake fluids that are capable of absorbing water from the air. DOT3 is Glycol Ether Based. The benefit of using Glycol Ether is its high boiling point with a lower molecular weight. DOT3 is a very commonly used brake fluid because it is the most economical when it comes to meeting the government standards.


Is the next brake fluid that can absorb water through the air, when handling both DOT3 & DOT4. it is important to limit the exposure to the air. Also you don’t to spill any of this on your car because of the chemical properties of the Glycol Ether.

Only open the brake fluid reservoir when necessary, make sure you seal the plastic bottle tightly. DOT4 has a high stability and a high boiling point when its new.

If, water is absorbed into DOT4 the boiling point drops rapidly, even more than DOT3. DOT4 is referred to as a race or performance brake fluid because of the viscosity limit. Therefore when it comes to performance vehicle it is important to change your brake fluid more frequently.


Unlike DOT3 and DOT4, DOT5 fluid doesn’t absorb water.

DOT 5.1 is also hydrophobic which means non absorbing and is used because of the lower chances of corrosion. DOT 5.1 used to be exclusively in the high performance industry because it requires so much attention.

DOT 5 has its benefits of being silicon based, it won’t chip paint if you spill it on your car. When pouring DOT 5 you have to pour slowly. Pouring too fast will create air bubbles and this will put gas in your brake lines which will leave your vehicle at risk.

If your vehicle is use as a sunday driver it almost certainly will have to be bleed after every time you let it sit for a long time. The moisture in the brake lines pool at the lowest point which is normally in the caliper. This once again makes the fluid compressible and puts your vehicle at risk.

Best Race Brake Fluid

If you are an individual that likes making your own modifications to your vehicle you may find selecting the proper brake fluid a little tricky but it’s not.

Unless your vehicle is on a race track or a drift car your best option will still be a DOT3 or DOT4. This gives you an advantage of predictable gauge of how much your brakes can handle. You don’t have to change this fluid or bleed your lines as frequently as using any other brake fluid. In other words you have less chance of corrosion.

Best Brake Fluid

When it comes to brake fluid you have a very simple decision to make, but first, you have to decide what your intentions are. If you are just looking for something for your daily commute DOT 3 is for you.

Prestone AS400 DOT 3 Synthetic Brake Fluid

Is good for your light trucks and can be used on drum and disc brakes. Prestone as400 also has a high temperature stability which is a key factor when looking for a brake fluid. What helps to set this apart is the ability to flow at low temperatures and keep water from penetrating the hydraulic fluid.

HI-TEMP 570 Brake Fluid

Is best racing Dot 3 brake fluid and is engineered to be easy to use. HI-TEMP has a low viscosity which helps with the bleeding and the flowing of the hydraulic brake fluid.

This helps with braking and maintain a long smooth brake pedal.  HI-TEMP formula helps the elimination of aeration in case of cadence braking and helps maintains a functional system.

Best Brake Fluid for Vehicles using DOT4

Motul RBF600 DOT 4 Brake Fluid

RBF600 some of has the highest dry and wet boiling points in the brake fluid industry. One thing that helps it stand out is the presence of nitrogen in the bottle rather than air which helps increase its shelf life and eliminate contamination. RBF600 is a racing brake fluid but can also be used for light range hauling trucks and cars.

Castrol DOT 4 Brake Fluid

Castrol DOT 4 Brake Fluid is a special European blend made for their temperate environment. This also has anti-vapor lock properties that helps keep the fluid dry. For those that live in a colder climate, this may appeal to you to help with moisture in the air.

Dot 5.1 Brake Fluids

Motul 100951 Brake Fluid DOT 5.1

Is a long life silicon based formula made for anti-lock brakes (ABS). This fluid has a lower viscosity so this enables it to travel easier through the micro-valves of anti-lock brake systems.

Braking (get it) It Down

Ultimately using the manufacturer’s recommended brake fluid is the way to go. If you’re an enthusiast driving a rare car around you will want to go with DOT5. You just have to keep in mind bleed your lines if it sat for a long time.

Nowadays most companies make a combination brake fluid. You can find DOT 3 and 4 anywhere. If you live in a very hot region and operate a military-like vehicle DOT5.1 is for you.

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