Brake Fluid – Buying Guide, Opinions and Analysis
Brake fluid is one of the most important safety components of any car, for this reason it is essential to carry out good maintenance and know how often it needs to be changed or checked, so that the car always has good braking capacity. Builders recommendations state that the brake fluid should be changed every two years, and since it is very easy to replace, you can do it yourself at home. In this article we will analyze some of the best brake fluids on the market, such as Brembo L 04 005, which offers you the confidence of the leading brake brand on the market, or Repsol RP701B96, a high-performance product with good stability. thermal.
The 9 Best Brake Fluids – Opinions 2022
Vibrations in the brake pedal, noises when pressing it or squealing, can be a sign that your car’s brake fluid needs to be changed. This element should not be forgotten, as it is easy to get used to poor braking, which in the end can lead to an accident. Next, we will analyze some of the best brake fluids on the market, so that you can choose the one that best suits your needs.
dot 4 brake fluid
1. Brembo L 04 005 Brake fluid dot 4
Brembo L 04 005 brake fluid could be the best brake fluid at the moment, since it has a higher boiling point than other cheaper fluids, which, together with its lower viscosity index, causes it to spread better and cover all parts, making braking easier and improving driving safety.
Thanks to the higher boiling point, it prevents vapor lock and offers efficient braking under all conditions. The fluid offers anti-corrosion properties and resists oxidation, so it can remain unchanged for a long time, extending the time between changes.
Brembo could be the best brand of brake fluid, due to its long experience as a manufacturer of safety parts for vehicles, especially brakes. This dot 4 brake fluid is suitable for any vehicle with ABS type brakes.
Prevention of vapor lock: Vapor lock is the formation of vapor bubbles due to the boiling of the brake fluid that, when compressed, push the pedal to the bottom, causing poor braking. The higher boiling rate of this liquid prevents evaporation.
Viscosity: Thanks to its maximum viscosity of 1400 cSt, it better lubricates all parts and improves braking performance.
Compatibility: It is a DOT 4 type brake fluid, so it has a very high compatibility and can be used in many car and motorcycle models.
Nozzle: The container does not have a dispenser, so care must be taken when pouring the liquid, since the nozzle is large and can be poured out.
2. Bosch Brake Fluid DOT4 0.5L
Bosch dot 4 brake fluid is made from synthetic materials, to offer the best resistance to heat. Thanks to this formulation, it prevents the formation of bubbles or vapor lock that can cause braking problems. Also, being a DOT 4 oil it is compatible with newer vehicles with ABS and ESP.
This could be one of the best brake fluids of 2022, as Bosch has been working for several years to offer a durable product, capable of withstanding up to 60,000 km in good condition and without showing signs of corrosion.
It has all the certifications of the OEM standards for cars of the Volkswagen group (Seat, Audi, Skoda and Volkswagen), PSA, Ford and BMW. Due to its formulation it is compatible with other brake fluids, so a complete drainage of the system will not be necessary.
Compatible: It is compatible with other brake fluids, saving you time as there is no need to drain the entire system.
Duration : Bosch brake fluid has a superior endurance, providing a prolonged maintenance frequency every 3 years or 60,000 km.
ENV 6: This type of brake fluid replaces DOT 3, DOT 4, DOT 4HP/LV and DOT 5.1.
Container: The plastic container is less durable than the traditional tin containers, since the liquid can degrade it and suffer losses.
hydraulic brake fluid
3. Repsol RP701B96 DOT 5.1 500ml
Repsol RP701B96 hydraulic brake fluid has been expressly designed for cars and motorcycles with hydraulic brake systems. It is a special lubricant for high-performance vehicles or those subjected to extreme conditions, so it is also the answer for users who are wondering which is the best brake fluid for competition or extreme use vehicles.
It is specially formulated for vehicles with ABS brakes and stability control systems. It offers great lubrication of the entire system, thanks to its low viscosity at low temperature. It has a very high boiling point, higher than that required by DOT 4.0 and 5.1 regulations, and additives that prevent the formation of foam and improve the life of rubber gaskets to prevent leaks, while lengthening the time between fluid changes..
Thermal stability: This brake fluid has great thermal stability, thanks to its low viscosity and its higher boiling point than other DOT 5 and 4 fluids.
Additives : Additives allow to take care of the health of the rubber gaskets, which prevents leaks and increases the time between each change.
Approvals: It has all the approvals such as SAE J-1703 and 1704, FMVSS 116 DOT 5.1 and DOT 4.0 and ISO 4925.
Compatibility: This brake fluid should never be mixed with other mineral- or silicone-based ones, so the reservoir must be completely emptied before changing.
4. Valeo 402402 Hydraulic Brake Fluid
Valeo 402402 hydraulic brake fluid is 100% synthetic, with a formulation that improves the boiling point, taking it up to 245ºC. This prevents the liquid from getting “toasted” by use, becoming thicker and therefore not working properly. In addition, vapor lock, the formation of bubbles in the fluid during braking, is also prevented.
This might be the best brake fluid for cars with hydraulic brakes as it is formulated to last so you can go longer between maintenance. It is also compatible with motorcycles, both for use in brakes and clutch, as long as the vehicle is compatible with DOT 4 type fluids.
It is a perfect fluid for everyday use, but not for sports vehicles or vehicles with intense use, in which it could cause inefficient braking.
Price: It is a very economical brake fluid with very good features, making it a perfect option to have as a spare or for an emergency.
Formulation : Thanks to its formulation it has better properties than some more expensive liquids.
Compatibility : It is compatible with most vehicles, whether motorcycles or cars, as long as they are compatible with DOT 4 type liquids.
Specifications: The certification seals do not appear on the bottle label and little information is offered on the formulation, as well as on the compatibility of the liquid, which can cause some mistrust.
motorcycle brake fluid
5. Castrol 15036B Brake Fluid for DOT 3 and DOT 4 Vehicles
Castrol 15036B motorcycle brake fluid is synthetically formulated to offer maximum performance to motorcycle braking systems. Castrol might just be the best brake fluid brand, thanks to its expertise in manufacturing lubricants and fluids for high-performance sports cars.
This brake fluid maintains braking efficiency for longer, thanks to its synthetic formula without minerals that “burn” and dirty the fluid. It has a higher boiling point, which far exceeds SAE J1730, SAE J1704, FMVSS 116 DOT 4, ISO 4925 and Jis K 2233 specifications. It is a fluid for high performance and competition vehicles.
It is manufactured with a mixture of polyalkylene glycol ethers and borate ethers, along with other high-performance heat-inhibiting additives, offering extraordinary protection to the entire braking system and protecting parts from corrosion.
Performance: It is a fluid formulated for high-performance or competition vehicles, whose parts are subjected to extreme operating conditions, making it very resistant.
Protection : This fluid ensures the highest level of protection for the brake system, prevents corrosion and evaporation of the fluid, avoiding the formation of bubbles.
Requirements : Meets all required standards for high performance vehicles.
Price: As it is a high-end brake fluid, designed for competition teams, its price is higher than that of other fluids on the list.
6. Repsol RP713A56 Moto Dot 4 0.5L
Repsol RP713A56 Moto Dot 4 motorcycle brake fluid is designed to protect and lubricate the hydraulic systems of competition motorcycles. Its synthetic formulation protects the parts from corrosion and torque, ensuring the maximum efficiency of each braking, as well as stable operation of the master cylinder.
It has a boiling point above 260 ºC, which protects the liquid from high temperatures and prevents it from boiling, forming bubbles, which can cause braking problems. It prevents the formation of foam and is highly resistant to oxidation, thanks to its corrosion-inhibiting components.
If you are wondering which brake fluid to buy for your competition motorcycle, this could be the one you are looking for, since it meets all the homologations and specifications.
Performance: This is a fluid designed for competition motorcycles or for vehicles subjected to extreme conditions, so it offers the best protection and the best properties.
Anti -corrosion: Thanks to its synthetic components that inhibit corrosion, this oil helps you keep the parts in the best conditions for longer.
Resistance : Due to its high boiling point and its protection factor against corrosion, it is a brake fluid that can last a long time.
Compatibility: This is a brake fluid formulated specifically for motorcycles, so it is not compatible with car brakes.
car brake fluid
7. Motul RBF 660 Racing brake fluid 0.5L
Motul RBF Racing car brake fluid is perfect for all DOT 4 compliant vehicles. It is a fluid that can also act as a clutch fluid and has a silicone-free formulation, which prevents the formation of dirt inside and prevents the liquid from being “toasted”.
It has been designed to withstand extreme temperatures generated by competition brakes, especially those made of ceramic or carbon. Although it is also ideal for braking systems with conventional steel discs and for daily use. Thanks to its high boiling point, above 320ºC, it prevents the formation of vapors and bubbles, so it has a longer shelf life than other liquids.
Motul’s fluid exceeds all the requirements of the DOT 3, DOT 4 and DOT 5.1 standards, allowing effective braking, even in the most extreme conditions.
Formulation: Despite being a synthetic oil, its silicone-free formulation is less polluting.
Compatibility : It is a fluid compatible with motorcycles and cars, as well as for use in clutches, so it can be very useful in many circumstances.
Protection: It has a boiling point of 328 ºC, much higher than that of most liquids, making it a high-performance product.
Quantity : For a high-capacity brake fluid and for its price, the bottle could be a bit larger, since 0.5L is a bit short.
8. Castrol React Performance Brake Fluid DOT 4 1L
Castrol React Performance car brake fluid is indicated for most vehicles compatible with DOT 4 type fluids, whether they are cars, motorcycles or vans. In addition, thanks to its synthetic formulation, it can also be used to replace the clutch fluid, as long as it is vehicles with hydraulic systems.
It is a totally synthetic product, so it offers the best performance, with a very high resistance to extreme temperatures that form inside the brake system. This prevents the formation of foam and bubbles, which can cause poor braking.
In addition, being designed for competition and high-performance vehicles, it prevents corrosion and protects the entire braking system, improving the useful life of the oil and also of the brakes. Meets all FMVSS 116 DOT 4, ISO 4925 Class 4, and SAE J1703 and J1704 specifications.
Bottle: The bottle has a transparent part on one side, which allows you to control the amount of liquid that is left. In addition, the cap has a diffuser that prevents accidental spillage.
Performance: It is a high-performance product, which facilitates the best braking even in the most extreme conditions of the competition.
Compatibility: It is compatible with most DOT 4 vehicles such as cars, motorcycles and vans, as well as for use in clutch fluid changes.
Price: Being a high-performance brake fluid, it is priced somewhat higher than other products for daily use.
Brake fluid DOT 5.1
9. Motul Brake Fluid DOT 5.1 0.5L
Motul’s DOT 5.1 brake fluid has a synthetic formulation that provides extra protection to all components of the braking system. With a boiling point of 272 ºC, it is capable of withstanding extreme temperatures without burning or “browning”, and it also prevents the formation of bubbles and foam, which cause braking problems.
Motul’s could be the best price-quality brake fluid, as it offers very high protection, making it perfect for any vehicle with a hydraulic system with very high braking demands.
It is compatible with cars, motorcycles and even bicycles, as long as they are compatible with DOT 5.1-type fluids, so it is ideal for replacing the DOT 4 brake fluid that cars usually have from the factory and that offers worse performance than this..
Compatibility: It is a perfect oil for a wide variety of vehicles, from cars to bicycles, as long as the brakes are compatible with DOT 5.1 fluids.
Effectiveness: It is a product with many properties, which is why it offers maximum safety and protection, with safe braking.
Duration: It has a high boiling index, as well as protection factors against corrosion, so it can last a long time without degrading.
Quantity: To change the brake fluid of a car, you need to buy two bottles, since 0.5L will not be enough for a complete change.
Brake fluid accessories
brake fluid reservoir
Febi-Bilstein 26658 Brake Fluid Surge Tank
The Febi-Bilstein brake fluid reservoir is made of high-quality plastics, making it highly resistant to shocks, scratches and temperatures, so it won’t melt or warp when the fluid gets hot or boils.
It fits perfectly in its space, although it does not have the rubber gaskets, which must be purchased separately to avoid spilling or losing the liquid. The cap has a safety thread to prevent liquid loss and is compatible with most Audi and Volkswagen cars.
brake fluid tester
beley brake fluid tester
The Beley brake fluid tester allows you to analyze the condition of the brake fluid, checking the ratio of water within the fluid, which helps you to better maintain your car.
It has a flexible gooseneck probe 250 mm long, with a chrome-plated surface to resist corrosion caused by products. The 2.2-inch LCD screen with backlight shows all the information, arranged in a simple and intuitive interface.
It has a double buzzer and red light alarm system. The fit is universal, suitable for most vehicles and for DOT 3, DOT 4 and DOT 5 fluids.
After our comparison of brake fluids in which we have analyzed in detail the best products, we are going to move on to the buying guide, in which we will explain what are the most important points that you should pay attention to before buying a brake fluid for your vehicle.
We start this guide to buy the best brake fluid with one of the most important points and that is that not all fluids on the market are the same. It is very important to use only the type of liquid indicated by the manufacturer. To find out what it is, the best thing you can do is consult the manual or ask directly in your trusted workshop.
Nowadays, many cars circulate with the fluid in poor condition or use the wrong fluid, which can cause accidents and braking problems.
In the market we can find DOT 3 type liquids, which is the most conventional liquid, they have a dry boiling point of 205 ºC and a wet boiling point of 140 ºC, so they have relatively low points, which leads to the formation of foams and bubbles. Its viscosity is usually around 1500 cSt (viscosity units) and it is a common and cheap liquid, although practically in disuse.
DOT 4 is the most used in ABS type brakes, so it is the most common fluid today and the one that all cars usually carry when they leave the dealership. It has a dry boiling point of 230ºC and a wet boiling point of 155ºC, although some high-performance DOT 4s exceed these numbers. Its viscosity is 1800 cSt and it offers greater durability than DOT 3, so it can be changed every 60,000 km or 3 years, although it is not recommended.
DOT 5 type brake fluid is the most used in American cars, it is a product whose synthetic-based formulation does not use minerals, so it produces less waste and pollutes less. This liquid should never be mixed with DOT 3 and DOT 4 liquids, since these do contain mineral elements in their formulation. Due to its synthetic base it is very resistant, with boiling points above 260 ºC.
Finally, we find the DOT 5.1 type liquids. Contrary to what it may seem, it is not an evolution of 5.1, but rather a completely different liquid, with a mineral base. It has a dry boiling point of 270ºC and a wet boiling point of 180ºC, with a much lower viscosity than that of other liquids, 900 cSt. The main advantage of this liquid is that it has a greater hygroscopic power than that of DOT 3 and DOT 4, which means that it absorbs moisture better, protecting the liquid for longer.
Boiling point is another very important factor to look at when choosing a brake fluid and it will have some impact on how much the product itself costs.
This characteristic is decisive to avoid the maximum temperature effort, since when this point is exceeded, the liquid begins to boil and vapor bubbles form, making it no longer stable and causing vapor lock that prevents the car from braking correctly. When this happens, the pressure point of the pedal varies and can even be lost with disastrous results.
Brake fluids have two boiling points: dry and wet. The first is the boiling point of the new and sealed liquid, and it is usually around 240 for a cheap liquid or 300 ºC for competition liquids. The second is the boiling point of the liquid when it contains 3.5% water, something common due to condensation and possible leaks that cause water to enter the tank.
Brake fluids usually have two basic formulations to choose from: glycol-based or silicone-based. Glycol-based liquids have a better hygroscopic factor, that is, they bind and absorb water. Those based on silicones do not have this positive property and, therefore, tend to have a lower performance.
Viscosity is the factor responsible for ensuring the functions of the braking system. The use of modern ESP braking and ride stabilization systems require a high rate of modulation and brake pressure.
For this reason, the best brake fluids have a particularly low viscosity, as this is the prerequisite for reliable control and instant braking. Using a fluid with the wrong viscosity can have fatal consequences on brake performance.
Frequently asked questions
Q1: How to change the brake fluid?
The process of changing the vehicle’s brake fluid is somewhat more complex than changing other fluids, such as oil. The main cause is that we not only have to change the liquid, but also bleed the system, so that everything works correctly. We will start by parking the vehicle in a flat area. We open the hood and look for the liquid reservoir, which we will empty using a syringe or vacuum cleaner. Next, we add the new liquid, taking as little time as possible in the process to reduce the presence of air.
The next step is to bleed the brakes. To do this, we will remove the wheels, one at a time and starting with the rear left. Then, we will continue with the right rear, left front and right front. This order is important and must be respected. Each brake caliper includes a bleeder in the cylinder, which we must open and connect a rubber hose to collect the old fluid. For purging, you must help another person, who will step on the brake several times to “charge” the system and then step on it all the way, opening the bleeder first. It collects the excess liquid and, once the pedal is fully down, the bleeder is closed. At the end of the process, we must check the liquid level and add more if necessary. We will repeat the process with each brake until completing all four, finally verifying the level.
Q2: When to change brake fluid?
As with oils and other engine fluids, the maintenance interval appears in the manual of our vehicle, this being the main reference in this regard. If you do not have the manual at hand, a maintenance period of about 30,000 to 40,000 kilometers is generally established. Since it is an economical and vital operation for our security, it does not hurt to execute it with an adequate frequency.
Q3: What happens if I run out of brake fluid?
Since the vehicle’s brake system is hydraulic, what we will notice at the moment is that, when pressing the pedal, it will go to the bottom without any effort, since this lack of fluid eliminates the resistance of the pedal. Obviously, the brakes will not work either, since there is no internal pressure in the system, they will not activate and you will not be able to stop the vehicle normally. In this case, you will need to use the gearbox to slow the vehicle down, using the parking brake when the speed is slow enough to stop safely.
Q4: Where do you put the brake fluid?
The brake fluid is poured into a tank located inside the engine compartment and duly labeled as such. Its size is small, similar to that of a small jar, so you will have to sharpen your eyes. If you can’t find it, you can always refer to the user manual, where its specific location is indicated.
Q5: What color is the brake fluid?
New brake fluid is clear and has a golden yellow hue. As it is used, it takes on an increasingly darker color to the point of turning black if it is of considerable age. This color is precisely one of the useful references to know if it is time to change it.