How Long Does It Take for Brake Fluid to Work?

Brake fluid is a clear, colorless fluid that’s used to transfer the force of your foot pressing down on the brake pedal to the hydraulic system of your car. That hydraulic system then acts upon the brakes themselves and slows you down.

The hydraulics in your car is powered by pressurized air, so when you press down on the brakes, the air pushes against the brake fluid. As this pressure increases, it forces more brake fluid through the lines connecting your foot to the hydraulics. This causes them to push against each other and slow down your vehicle.

Brake fluid doesn’t do anything until it gets wet. When exposed to moisture or water, it dissolves into its base chemicals: glycerin and water. These chemicals then turn into soap that lubricates metal parts such as pistons or cylinders inside your braking system so they can move freely without any friction between them.

What does brake fluid do?

Brake fluid is a chemical mixture that helps your car’s brakes work. It also serves to lubricate the brake system and absorb heat. The brake fluid in your car is stored in a reservoir, and it slowly moves through the brake lines when you press down on your brake pedal.

Once it reaches the calipers, where it’s needed most, it pushes against the pistons inside them, causing them to squeeze against your car’s wheels. This action slows down the rotation of your wheels, bringing you to a stop.

When you depress your brake pedal, you’re essentially forcing fluid into those pistons. To make sure that this happens smoothly and consistently, you need to keep your brake fluid clean.

How can you tell when your brake fluid is low?

Depending on how much you drive, your brake fluid might need to be changed every 6 to 12 months. You can check it by looking at the level in your reservoir and comparing it to the maximum line on the side. If it’s below that line, you’ll want to add fluid before driving.

Make sure that your car is parked on a level surface—you don’t want any air in the reservoir. Then open up the cap and remove the old fluid with a clean funnel or turkey baster. Make sure that you don’t spill any of this stuff on yourself or other surfaces, as it can damage plastic parts on your car.

Do you need to flush the system before you change your brake fluid?

If you’re replacing your brake fluid because you have a leak, then it should be immediately effective. If you’re just adding new fluid to an existing system, then it can take anywhere from a few hours to several days before the new fluid is up to full pressure and functioning as well.

If you’ve been driving around with low brake fluid for a while, then this could mean that some of your pistons are already damaged or worn down enough that they can’t squeeze any harder than they already are and that’s why your car doesn’t stop as quickly as it used to. That’s why it’s important not only to check your levels regularly but also to make sure that the car is in good repair before adding new brake fluid.

What kind of brake fluid should you use?

When you’re looking for brake fluid, it’s important to make sure that you’re using the right kind of brake fluid. The wrong kind of brake fluid can cause a number of issues, from damage to your car’s brakes and other systems to a complete loss of functionality in your brake system.

It’s also crucial to make sure that you’re using the correct amount of brake fluid if you use too much or too little, it could cause damage to your car’s brakes or other systems. If you have too little brake fluid in your system and then have an accident, it could cause the brake system to fail completely because there isn’t enough fluid left in the cylinders to generate enough pressure to stop your vehicle.

On the other hand, if you have too much brake fluid in your system, it can lead to leaks around seals which will eventually cause them to fail completely and require replacement or cause corrosion on metal components like hoses and lines that connect them together.

How often should you change my brake fluid?

If your brake fluid is dirty or low, you might be able to feel a squishy feeling in your brake pedal as you’re driving. If that happens, pull over and check your fluid level immediately. You should also check the level if you notice any signs of leakage under your vehicle.

You should always change your brake fluid at least every two years, especially if you drive in areas with high temperatures or humidity. If you drive in those conditions often, consider changing it every year instead of every two years.


Brake fluid works instantly. It is an incompressible liquid with low viscosity and a high boiling point. It has a very low specific heat capacity, which means it can absorb more heat than many other fluids. The brake fluid in your car has been designed to provide quick action under high temperatures, so it will act faster than any other fluid could ever hope to.

Steven Hatman
Steven Hatman

We break down every information into easy-to-understand articles that cover all the categories anyone who owns a car needs to know about, such as oil , brakes , tires and etc. Our car guide is free and updated regularly for you to use as a resource, not only when you have an issue with your car but even before buying a new or used car! We also give tips on what to look for in each category or part of your vehicle.