Brake Fluid Flush: Why you need it and what it costs

To keep your vehicle in peak condition, there are many routine maintenance tasks you should perform. A regular brake fluid flush is one of your most essential tasks. What’s involved in the brake fluid flush and why should it matter to you?

We will be discussing this vital maintenance task in this article and evaluating its cost. This article also explains how you can flush your brake fluid yourself at home. 

What exactly is a Brake Fluid Flush and how does it work?

All old, contaminated fluid from your brake system is removed during a brake fluid flush. It’s replaced with fresh, clean fluid to ensure superior braking ability. The fluid change is typically done once every 30,000 miles, or twice every two years, depending on which comes first. 

It’s just as important to regularly check the brake fluid levels. If the system doesn’t have enough clean brake fluid, there can be performance issues that put your safety at risk.

How to flush your car's brake fluid

Many components of the brake system must work together to achieve superior performance. Whether the car has disk brakes on all four wheels or it contains drum brakes in the back, it’s still connected by tubes and hoses that link each brake to the master cylinder. 

Pushing down on the brake pedal pushes the plunger into the master-cylinder. Brake fluid then runs through the connectedhoses to each wheel's brakes. This fluid is pushed into the master cylinder for disk brakes. The piston applies pressure so that the brake pads grip the disc and slow the wheels down. Drum brakes use fluid to push into the wheel cylinder. This allows the shoes to apply pressure on the drum, stopping the wheels from moving. The fluid will be required to provide braking power in any way.

Components in the brake system can begin to wear over time. Brake fluid can become polluted by debris, rust, rubber and other contaminants. As the fluid becomes dirty, it’s less able to perform its job, leaving you with brakes that don’t work properly. 

Also, brake fluid has a high hygroscopic property. The fluid absorbs water and its effectiveness decreases with age. Plus, the metal components don’t hold up well against this moisture and can easily corrode. 

RELATED: 5 Symptoms of a Brake Fluid Leak (& Repair Cost)

Brake Fluid Flush Cost

Average brake fluid flush prices range between $75 and $250. This price covers both labor and parts. It is possible to save money by doing the brake fluid flush yourself.

Costs will vary depending on where you live and how much labor is required. This can depend on the year, make and model of your vehicle. 

You need to flush your brake fluid.

1. Mileage

There’s plenty of debate over how often a brake fluid flush should be performed, but most car manufacturers will outline the recommendation in the service manual. If you are unsure, it’s best to follow the 30,000-mile or 2-year standard.

How you drive will affect your maintenance needs. Regular flushes may be more important for those who commute to work in cities with a lot of braking. 

Related: DOT3 vs. How to Mix DOT4 Brake Fluids

2. Spongy Brake pedal

You should change your fluid immediately if you feel the brake pedal becoming spongy. You should not leave this problem unattended. The pedal can start to slide all the way to the ground, which could be very dangerous.

Air can get into the system when the fluid is contaminated or becomes less liquid. What you are left with are brakes that don’t respond the way they should. 

3. ABS Light

Anti-lock brakes prevent your wheels locking up in the event of loss of traction. There’s an ABS warning light on the dashboard that indicates when there’s a problem with the system.

ABS lights might be activated if brake fluid gets low or is heavily contaminated. To compensate, the ABS light will turn off. 

4. Brake Performance Reduced

Normal circumstances will allow the brakes to work quickly and effectively. When you press the brake pedal to stop, there should not be any delays. A brake fluid flush may be necessary if there are any delays.

But performance problems can be caused by worn out brake pads or warped rotors. If you are unsure, it’s best to have someone perform a brake system inspection. 

5. Noises/Smells

Whenever there’s an issue with the brake system, it can be caused by a worn component or low brake fluid. It’s possible to even deal with grinding or scraping, although these normally point to worn-out parts.

Burnt fluid or contaminants could be causing burning smells during braking. To ensure safety, you should stop driving if there is any burning sensation. 

How to perform Brake Fluid Flush

1. Get rid of old brake fluid

The master cylinder must be drained of all fluid. There’s no drain plug to the system, so you will need to use a siphon pump or transfer pump.

You can also use a turkey baster or a bigger syringe if all else fails. You can continue removing fluid until you empty the reservoir. You can do this with the engine off. Keep the car in Park. Make sure you don't press the brake pedal. 

2. Fill the System & Bleed

You should fill the reservoir with new brake fluid. The system will be bled in the exact same manner as when new brake calipers are installed.

Starting at the back, bleed both the rear calipers and wheel cylinders. The corresponding bleeder screws can be opened by pushing down on the brake pedal. Once the pedal touches the ground, release it and close the bleeder screws. Keep going until the entire system is empty.

Now you can move forward after the back brakes are removed. The same process applies to the front brakes.

3. Top Off & Test

You must first check each wheel for fluid leakage after you have bled it. Once you're done bleeding the brakes you should top it off. 

You should test drive your car before driving out onto the open road. It’s best to find an empty parking lot or somewhere uninhabited to test the brakes out before using them in the real world.