Many drivers indeed underrate braking system maintenance. They just come to the repair shop when the pads or rotors perform badly or are broken.
Maybe they heard of the brake fluid flush. But how much brake fluid do I need to flush? Many don’t know.
If you also have no idea about the issue and how important it is, don’t worry! We’ve got your back! Keep reading to figure out the answer!
About Brake Fluid
What Is It?
Before getting to know how much brake fluid for flush, let’s find out what the liquid is.
It’s a type of hydraulic liquid used in the stopping system of vehicles. Its main usage is to transfer force into pressure.
The appreciably incompressible liquid intensifies the halting capability; thus, the system works smoothly.
The four most common types are DOT 3, DOT 4, DOT 5, and DOT 5.1. They generally have an glycol-ether base, accounting for 75-90% according to Science Direct.
But the dry boiling capacity and the wet boiling capacity are different. DOT 3 is suitable for regular drivers, whereas DOT 4 specializes in racing and performance cars.
How Does It Work?
Besides caring about how much brake fluid to replace, it’s interesting to know how it works.
The car braking system consists of different components. Usually, you have front disk brakes and rear disk brakes, or rear drum brakes.
They are connected to the main cylinder by tubes and hoses. When you apply pressure to the pedal, there’s a force against the cylinder, rendering the liquid to each wheel’s brake.
If your car is drum brake type, the liquid is pushed to the wheel cylinders, causing the brake shoes to fall against the drum and forcing the car to slow down.
In case of the disk brake type, the liquid goes to the caliper. In turn, the caliper pushes against the piston where the pads are held back and stops the vehicle.
Now, how much brake fluid do I need to flush car?
How Much Brake Fluid Do I Need To Flush?
How many ounces of brake fluid do I need? The answer is you need one quart or 32 ounces to replace the entire dirty and discolored old fluid.
You should do it as it’s one of the important parts of your car maintenance routine.
Is The Flushing Process Necessary?
The amount of fluid needed for flush is revealed, and there are some reasons to explain why you need the process.
Firstly, your brake system consists of many metal parts, while the hygroscopic attribute of the liquid makes it absorb moisture, leading to the corrosion of the components.
For example, the corrosion in the cylinder will damage the piston.
How much brake fluid in a car is not a fixed number. Because the liquid attracts atmospheric moisture, it absorbs 3% of its weight each year.
Eventually, you will not have 100% of 32 ounces, making flush more necessary.
Secondly, the liquid gets dark due to water contamination, lowering the boiling point remarkably. It badly influences the halt capability and blocks the system from responding to every bit of pressure.
Lastly, the braking process also produces heat, affecting the liquid. In reverse, the anti-lock system and traction control components are easily ruined by the dirt particles in the flow.
You need to spend much more money to fix them than to do the flushing. Flush with fresh liquid can restore additive package levels and preserve the system at the comfort level.
How Often Should You Flush The Brake Fluid?
It’s important to know how much brake fluid to bleed system, but it’s also vital to know how often you should do it.
It’s suggested to change it every two to three years or when your car reaches 24000 to 37000 miles, depending on what condition comes first.
If you have a sports car, every 3100 to 6200 miles is the ideal milestone. However, you should diagnose your car’s real conditions to decide the flush time.
For example, if your car shuts off when you press the brake, there is a good chance that the brake fluid is leaking and needs a flush.
Can You Do The Flush By Yourself?
Yes, you can do it yourself if you have some knowledge and experience with automobiles.
The job is not too difficult, and no special tool is needed. However, ensure you work on it carefully to avoid further problems.
You now know how much brake fluid to flush, but remember to read the vehicle owner’s manual to search for any special requirements for the types and the process.
Notice that the combination of water vapor from outside air with the fluid can ultimately damage the system as the liquid is contaminated.
If you think it’s overloaded, book a custom maintenance schedule and bring your car to a mechanic for faster and more professional service.
The cost depends on the type of liquid, the auto repair labor costs, and whether they use the decontamination procedure.
How To Flush Brake Fluid?
Before flushing your brakes, ensure the fresh braking liquid is ready. It’s important to pay attention to its shelf life.
You cannot use it for the task if you have opened it for more than two weeks. The reason is that an unsealed one contains moisture content, which makes the whole process useless.
How much brake fluid do I put in my car? Again, you should prepare one quart or 32 ounces of the fresh one. Now let’s start!
Step 1. Park your car on a flat surface, put it in gear, and place something behind to prevent the wheels from rolling.
Step 2. Open the hood and find the master cylinder containing the braking liquid. Take out its cap and wrap a piece of rag outside to avoid some spillage.
Step 3. Use a turkey baster to extract the old fluid into a container. Usually, you can drain off around 80%, and it’s fine.
Step 4. Fill the reservoir with a fresh one. The type of liquid is decided by its boiling point. Make sure you choose the right one for your vehicle.
Step 5. You should figure out the order of bleeding the calipers. For example, if your cylinder is in the engine by the driver seat, the order will be the rear passenger seat, the rear driver seat, the front passenger seat, and the driver’s side.
As you can see, the sequence starts from the farthest wheel (compared to the location of the reservoir), and it’s considered a norm. However, make sure you double-check it with the manufacturer.
Step 6. Once you define which caliper to start with, jack up that side of the car, remove the wheel, and approach the caliper.
Step 7. Use jack stands to hold the car, and you may need a pressure bleeder. Put the rubber hose over the bleeder valve to absorb the dripped fluid. Choosing the correct brake bleeder hose size is a must.
Step 8. Have an assistant help you push the brake slightly a few times and notify you of any stiffness. When they are pressing the pedal, open the valve so the liquid can come out. The assistant will tell you to close the valve right before the pedal goes all the way down.
Step 9. Keep going on the process until you see the color difference. Alternate colors from a dark color to the lighter one leave the bleed valve, which means that the brake line is filled.
Step 10. Repeat the same with the other three corners. The correct procedure is important. Remember never to let the fluid be lower than the minimum line in the cylinder; otherwise, the air may come inside the system, and you have to start again.
Step 11. Once you complete all steps for each side, pump the pedal to top the liquid to the maximum line in the reservoir. Double-check to ensure you have everything in place.
Apart from flushing, you need to perform other maintenance procedures. For example, when you find the brake pedal squeaking, it’s time to bleed the system.
Bottom Line
How much brake fluid do I need to flush? After all, this shouldn’t be a question for you anymore.
Remember, maintenance of the brake is as important as the maintenance of other components.
You’d better stretch your budget a little bit for one quart of fresh fluid before the old fluid damages the other parts in the braking system.