Understanding Brake fluid flush And Why It Is Necessary

Driving with healthy brake fluid is a huge price many pay for their safety without even knowing. Brake fluid essentially helps convert pressure into braking force to stop your car. In good condition, the fluid should act as intended. If, however, it gets contaminated or too old, it may not be able to function as intended.

Here, you may have a spongy pedal which can terrify you or even be dangerous when trying to stop the car. Hence, the need for a brake fluid flush. Typically, one can change the fluid and still have a good running brake system. But people may prefer flushing due to its benefits. So what is even a brake fluid flush?

brake fluid flush near me

What is a brake fluid flush?

A brake flush is a process of removing all old contaminated brake fluid from the system and replacing it with a fresh one. This doesn’t just let you have a clean fluid but also keeps the fluid’s housing and transfer channels clean. This allows it works effectively when stopping your car. Most manufacturers recommend adding a brake fluid flush to your maintenance routine.

Is a brake fluid flush really necessary?

Many have asked, is a brake fluid flush really necessary? Yes, and here is why. Your car’s braking system comprises several components that collectively bring it to a stop. But in all this, the brake fluid plays a vital role in supplying braking force. In a disc braking system, the brake fluid in a tube helps transfer hydraulic pressure to the caliper. ,

Invariably squeezing the piston against the brake pad, which in turn pushes against the disc rotor to stop your car. In a drum braking system, the tube filled with brake fluid supplies forces to the wheel cylinder housing the piston. This pushes the pistons against the brake shoes, which then presses against the brake drum to stop the car.

Looking at both scenarios, the brake fluid is an asset. However, it must be clean to do this. But as time goes on, it picks up small pieces of dust and other contaminants from other braking components, making it dirty. A dirty fluid will not provide enough braking force to stop your car, which can be terrifying.

Brake fluid, due to its hygroscopic nature, also absorbs water making it less effective.

The heat generated during the braking process can also break down the fluid. Hence the need for brake flush. Typically, a brake fluid flush keeps the brake fluid, it’s housing, and transfer hoses clean.

Invariably resulting in better braking performance and also keeping you safe. It also lessens the risk of brake fading and the risk of the caliper or wheel cylinder failing, which invariably makes them last longer and saves you money.

How to flush brake fluid

Brake flush can be left to professionals as they have all the right tools and equipment to make the process easy and faster. However, it does cost money to do it. So if you are doing it yourself to save cost, ensure you know your way around. Start by getting the manufacturer-recommended brake fluid; you should see this in your owner’s manual.

Also, get your brake fluid flush kit by your side. The kit should contain a brake bleeder, a digital multimeter, an open-ended spanner, etc. Lastly, this job is best done by two people. So ensure you have someone with you when doing a brake flush. With all ready, do follow this process.

Prepare the car

Park your car on leveled ground, put it in gear, then set a wheel chock or its alternative behind the tires to avoid rolling.

Locate the master cylinder reservoir.

The master cylinder houses the brake fluid, open the hood of your car and locate the master cylinder. The brake fluid color should be light yellow, but it changes as it ages. You don’t want to waste brake fluid that is still in good condition. Therefore, you can test the brake fluid condition with a brake fluid tester to decide whether the brake fluid is still good or not. If the test confirms that the fluid needs replacement, then, proceed to the next level.

Remove fluid from the master cylinder reservoir.

Suck out all the brake fluid in the master cylinder using any of these: transfer pump, large syringe, small siphon pump, turkey baster, etc. However, this process may not remove all the fluid; likely, about 20% may still be there. But don’t worry about it.

Fill with fresh fluid and bleed.

Fill the reservoir with new brake fluid, then start bleeding the brakes. You can start with the back caliper/wheel cylinder and then move to the front. To get a good view, jack up the side of the car you want to bleed by about 2 feet high and support it with jack stands. Remove the wheels to access the caliper/wheel cylinder and bleed.

To bleed, locate and remove the bleeder valve (this valve helps prevent spillage) and attach the brake fluid flush tube. Ask your partner to pump the brake pedal; while doing so, open the bleed valve to drain out the fluid.

When all the rusty brown fluid is gone, and you start seeing fresh fluid coming out of the tube, know that the old fluid is all gone. Repeat this process for the other wheels. And for every wheel you bleed, always check the master cylinder reservoir. However, if there is no brake fluid coming out when bleeding, you possibly have a faulty screw bleeder valve, caliper issues, a clogged brake system, and air or air bubbles in the system.

Top it off

With all four wheels done, pour more brake fluid into the reservoir until it reaches the fill line. After that, check the brake fluid level on the reservoir and ensure there’s no brake fluid leak anywhere in the system.

brake fluid change

Frequently Asked Questions – FAQs

Q: What happens if you don’t flush the brake fluid

Brake fluid gets heated during braking, absorbs water because of its hygroscopic nature, and gets contaminated by other brake components. All these actions tend to reduce its viscosity and efficiency, which invariably affects its effectiveness.

Therefore, not flushing brake fluid will let it stay contaminated, invariably causing brake fade and risks caliper/wheel cylinder failure, leading to repair costs. Moisture in the brake fluid can also lead to corrosion of the hydraulic system and other problems.  These can reduce braking performance and even cause brake failure in critical driving conditions–a very dangerous and terrifying situation to experience.

Q: How much does it cost to flush brake fluid?

Brake fluid cost depends on who is doing the flush and your vehicle model. If you’re doing it yourself and have a smaller brake fluid reservoir, it should be less than someone with a bigger reservoir or doing it at a mechanic. But generally, brake fluid costs around $70-$110 for most vehicles, with most of the price going into labor. Here is a comparison of some popular auto shops.

Midas brake fluid flush price lurks around $57-$94 for parts and labor, with a year warranty. Whereas Pep boys will do this for about $69-$85 with a six months warranty. Similarly, Your mechanic can flush brake fluid for around $79-$89 with a year warranty. Mr. Tire, however, will do it for about $83-$95 and accompanied by a 12 months warranty.

It can be way cheaper if you’re doing it yourself. You only need to purchase the manufacturer-recommended brake fluid costing about $8-$30, and get a brake fluid flush kit. And even cheaper if you already have the kit. But have it in mind you will spend more time compared to doing it at a mechanic shop.

Q: How often do you really need to flush brake fluid?

Brake fluid flush, how often should you do it? Brake fluid flush should be done every two years or 30k miles, whichever comes first. Better still, stick to your manufacturer-recommended interval. If, however, you drive regularly, you may have to do it earlier than required. In this situation, carrying out a visual inspection to ascertain the condition of the fluid will be a better idea.

Q: How long is brake fluid good for?

If already inside your vehicle, it should still be good for the next two years or 30k miles. If, however, you opened a newly purchased brake fluid, it is expected you shelve it for only 12 months.

Any fluid that has stayed more than 12 months in its container may have been contaminated by air, dust, or moisture. And therefore not suitable for vehicle use again. At this point, you may need to discard it.

Q: How long does a brake flush take?

A brake fluid flush generally lasts 15 minutes to 1 hour or more, depending on your approach. If you’re doing it yourself, it may take longer than when a mechanic does it. This is true because these mechanics do not use the normal bleeding process but utilize a brake fluid flush machine.

A professional mechanic can have this done within 15-30 minutes with this machine. If, however, you consider brake fluid flush waste of money, you can do it yourself. But this should take up to an hour or more.

Q: Can you mix old and new brake fluid?

If the old fluid in the system is low but not contaminated, you can add new brake fluid to the old one. But ensure the new fluid is the same as the old one.

If, however, the old fluid is contaminated or lingered for more than two years, adding new fluid will be a waste of time and resources as the old fluid will also contaminate the new one making it ineffective. Here, your best bet will be to go for a complete brake flush. Drain off all the old fluid before pouring in the new one.

Q: Does brake fluid need changing every 2 years?

Most manufacturers recommend changing brake fluid every two years or 30k miles. However, some also recommend changing it every three years or 45k miles. So your best approach is to follow your manufacturer-recommended interval, which should be indicated in your vehicle owner’s manual. It is also essential to distinguish brake fluid flush vs. change.

Generally, brake flush is removing all the old fluid from the system and replacing it with a new one. This way, the system is totally free from any contamination, though it takes longer. However, brake fluid change isn’t done the same way as flush. In brake fluid change, only a large portion of the old fluid is removed, so you will still have some old fluid in the system after adding the new one.

Q: Does Walmart do brake fluid change?

Walmart does not do brake fluid changes. However, if you surf the internet, you will find mixed answers. But going through Walmart’s service page, they don’t offer brake fluid change or any brake job. They, however, offer oil and tire change services.

And even if they do offer brake fluid change, you might not want to leave such a delicate part of your car for them to handle. According to users, Walmart technicians are underqualified as they can only handle a few parts. Users say they can’t do the job of real mechanics.

Q: What is included in a brake flush?

A brake fluid flush requires draining out all brake fluid from the system and replacing it with fresh fluid. Aside from the fluid itself, the entire system will also be clean. This includes the reservoir and brake fluid lines. Also, use this time to check the condition of other brake components like the brake pads, rotors, etc.

Complete Brake Flush and Bleed YouTube Video

Final words

Doing a brake fluid flush is essential to keeping you safe while driving and protecting other brake components, invariably saving costs. While doing a brake flush yourself will save cost, taking it to a professional mechanic will be much faster and cleaner since they use a brake fluid flush machine.

You can get a list of mechanics near you by typing brake fluid flush near me. Brake fluid, over time, can get contaminated with water, dirt, or air, making it less effective. This can damage the brake components, decrease braking performance or lead to brake failure. So for those asking, is brake fluid flush necessary? You now know the answer. It is necessary.

Osuagwu Solomon

Osuagwu Solomon is a seasoned automotive technician for the past 9 years, and a technical writer. He loves writing about auto professional repair guides, DIY repair guides, and buyer’s guide. After spending six years in the automotive workshop, he decided to impact his knowledge to people aside his domain, and he has achieved this by centering his Automotive writing skills on REPAIRS.

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