With so many different types of brake fluid, how do you know what to run in your car? This article covers the different types of brake fluids, what they're made of, and what you should run in your car.
How long does brake fluid last?
Generally all brake fluid types have a service life, and this is true for DOT 3, DOT 4, and DOT 5.1. They absorb moisture and should be replaced every 1-2 years under normal use. DOT 5 brake fluid does not absorb moisture, and technically it can be used indefinitely. We recommend replacing your brake fluid every 2 years or sooner.
What are the types of brake fluid and what are they made of?
- DOT 3:
DOT 3 is glycol based and glycol absorbs water (also known as hydroscopic). You should flush DOT 3 brake fluid every 2 years at the maximum. This is the brake fluid you will find in basic road-going cars, Toyotas, Hondas, Fords, GM, essentially cars that will not be driven hard enough to exceed the performance capacity of the fluid.
- We do not sell DOT 3 brake fluid.
- DOT 4:
DOT 4 brake fluid is also glycol based just like DOT 3 and should be replaced every 2 years as well. This brake fluid can be found in most European cars on the road today. This fluid is also found in almost every racing application.
- DOT 5:
DOT 5 brake fluid is silicone based instead of glycol. Since silicone is not hydroscopic, this brake fluid does not need flushing every two years. This was designed mainly for military applications specifically so that vehicles can sit for extended periods of time with minimal maintenance.
- We do not sell DOT 5 brake fluid.
- DOT 5.1:
DOT 5.1 brake fluid is glycol based as well and requires replacement every 2 years. The main difference between DOT 5.1 and DOT 4 brake fluids are both the wet and dry boiling points.
|Dry boiling point||Wet boiling point||Main ingredient|
|DOT 3||205 °C (401 °F)||140 °C (284 °F)||Glycol ether|
|DOT 4||230 °C (446 °F)||155 °C (311 °F)||Glycol ether/Borate ester|
|DOT 5||260 °C (500 °F)||180 °C (356 °F)||Silicone|
|DOT 5.1||260 °C (500 °F)||180 °C (356 °F)||Glycol ether/Borate ester|
Low Viscosity Brake Fluid:
This type of fluid is called for in newer European cars to aid in ABS, ESP, and TCS system performance. Essentially it is a thinner fluid which allows to be circulated through the ABS system faster. It does not last any longer. However, the performance gains are marginal. They can be mixed with non-Low Viscosity (LV) fluids; however, topping off with non-LV brake fluid should not be done as it brings down the effectiveness of the LV fluid.
Auto makers that call for LV fluid from the factory:
- Audi (2006 on)
- BMW (7/2002 on)
- MINI (all years)
- Saab (all years)
- Volkswagen (2006 on)
Auto makers that call for regular Non-LV fluid from the factory:
- Audi (up to 2005)
- BMW (up to 6/2002)
- Jaguar (all years)
- Land Rover (all years)
- Porsche (all years)
- Volvo (all years)
- Volkswagen (up to 2005)
Again DOT 3, DOT 4 and DOT 5.1 brake fluids can be substituted but need to be flushed completely. It all depends on your driving habits and what the car is used for.
Popular brake fluids we offer
|Dry boiling point||Wet boiling point||Link to product|
|Motul RBF 660
|325 °C (617 °F)||204 °C (400 °F)||MOTUL RBF 660|
|Motul RBF 600
|312 °C (594 °F)||216 °C (421 °F)||MOTUL RBF 600|
|ATE Type 200
|280 °C (536 °F)||198 °C (388 °F)||ATE Type 200|
|Pentosin Super DOT4
|265 °C (509 °F)||165 °C (329 °F)||Pentosin Super DOT4|
|BMW Brake Fluid
|265 °C (509 °F)||170 °C (338 °F)||BMW Brake Fluid|
(Low Viscosity) (Daily)
|265 °C (509 °F)||175 °C (347 °F)||ATE SL.6|
|Pentosin DOT4 LV
|265 °C (509 °F)||170 °C (338 °F)||Pentosin DOT 4 LV|
As with almost anything in life, more is better. The same holds true for the key numbers associated with brake fluid. The higher your boiling points the better. Keep in mind to select the fluid that works best for your application and style of driving.
If you daily drive your car chances are you need something close to what the original spec was. Most fluids that we sell meet or exceed factory specs. These fluids have a 2 year life span when used on the street.
What brake fluid should I run for the race track?
If you are tracking your vehicle or if it sees performance events, we have higher capacity fluids available. These fluids work better and longer under high-stress and high loads. It is suggested to replace the fluid once it over heats and begins to fade, or, once every 90 days. Most sanctioning bodies that hold events require at most 90 days since the brake fluid was changed prior to participating. One of the most-recommended racing brake fluids that we sell is ATE TYP 200.
Can I test my brake fluid to see if it's still good?
If you're unsure on the age of your brake fluid, or if you have overheated it and it's degraded to the point where it needs replacement, you can purchase a brake fluid tester.
Automobile aficionado. I really enjoy the engineering behind many of the automotive products out today. This includes mundane things which no one really looks at like filters, fluids along with suspension design and behavior. I also enjoy all things rare and produced in low numbers. Being a Service Manager at independent specialists and working at the dealership gives me valuable insight as to how cars get repaired, what products work, and what makes customers happy.