Are your brakes giving you trouble? Probably, you think there is a brake fluid leak. If so, you have come to the correct spot since there is a lot to discuss on this subject and we will learn everything there is to know about this issue.
A brake leak is a very dangerous issue. What makes me say this? Well, it’s relatively easy. Your car stops when you use the brakes. Without brakes around, you won’t be able to stop your vehicle in time and might get into an accident.
Other signs, such as a soft brake pedal and uneven brake pad wear, may also be present. All of this points to a potential leak. The post will go into more detail about the symptoms later.
Now is the time for you to roll up your sleeves and begin investigating the problem. You must learn how to analyze the problem and find a solution.
And by this, we mean that you must understand how this braking system operates and what parts make it up. You can quickly make connections if you are aware of this information. And we’ll assist you with this by thoroughly outlining it for you.
Next, we’ll discuss the potential reasons for this issue as well as the signs of a brake fluid leak. We will then immediately start diagnosing and resolving the issue. So, keep reading to discover more about how to solve this issue as soon as feasible.
Brake Fluid Leak: What Is It?
Let’s first go over the fundamentals before delving into the reasons and symptoms of a brake fluid leak. And that is the typical definition of a brake fluid leak.
For those who are unfamiliar with the subject and would like to understand more about this issue generally, this will be a very helpful introduction chapter.
Continue to the next chapters if you wish to learn about the causes and symptoms. If not, follow along with us.
Define a brake fluid leak then. Well, a brake fluid leak is a circumstance in which brake fluid is lost. Losing fluid is risky since it might lead to braking system problems and malfunctions.
You will have the most difficulty pushing the brake pedal. The system’s failure to respond will serve as a representation of these issues.
As you are aware, the hydraulic fluid in brake fluid maintains the proper pressure in the system. And it is because of this pressure that the braking system functions as it ought to.
Lack of fluid may cause issues since air will enter the brake lines, causing trouble. You will have problems if air gets within the brake lines. Since air, unlike hydraulic fluid, may be compressed when you depress the brake pedal. And the brake pedal will feel spongy as a result.
In addition, your car will be leaking brake fluid regularly, which has to be replaced if you don’t want your brakes to fail and cause an accident. Therefore, you should act if you observe a brake fluid leak and some of the signs that we will explain later.
The Functioning of the Brake System
Now let’s study how the braking system functions before we discuss the causes of brake fluid leakage. What exactly is a braking system? Your car’s braking system is what causes it to stop. You won’t be able to stop the vehicle without it.
This method uses hydraulics. indicating that hydraulic fluid is used to operate the braking system. When it comes to the effective working of the brakes, hydraulic fluid is a crucial component. You won’t stop moving without it.
This fluid frequently has the DOT logo. Different braking fluids exist, including DOT 3, DOT 4, and DOT 5. Depending on the application and the automaker, different fluids are used. You should refer to your driver’s manual that came with the vehicle for precise brake fluid.
Nevertheless, this method is straightforward to use. The master cylinder, which is located on the firewall, acts as the system’s brain. Some pistons in this master cylinder are in motion. These pistons move when you press the brakes, transferring the fluid via the brake lines.
The brake calipers then receive this hydraulic pressure that has been built into the lines. As you are aware when you apply and release the brakes, the pistons on each caliper open and close. These pistons pressurize the brake pads, bringing the vehicle to a stop. When the brake pedal is removed, they retract and allow the vehicle to resume motion.
It’s an easy procedure. But occasionally, even this method may go wrong. produced occasionally by leaks in the braking fluid, and occasionally by other factors. But what may bring about a brake fluid leak? Next, let’s go into further detail.
What are the Causes of Brake Fluid Leaks?
Let’s learn more about the sources of the brake fluid leak now that we have identified the issue. What potential factors might lead to the development of leaks? In the chapters that follow, let’s go into more detail about them. Later, we’ll also discuss the symptoms that are related to this issue.
1. Master Cylinder Leakages
The malfunctioning master cylinder is the primary likely source of the brake fluid leak. The master cylinder, which controls the pressure of the hydraulic fluid, is the brain of the braking system, as we have said.
You can put the vehicle in reverse with this master cylinder. However, there are several rubber fittings inside this master cylinder that might leak.
After several years of usage, the rubber just degrades and the master cylinder begins to leak. These leaks can be seen with the unaided eye. If the master cylinder is leaking and discharging braking fluid, you will probably see some grease stains around it.
It is advisable to give it a complete inspection to ascertain its state and whether the master cylinder is leaking. If so, a replacement must be made as quickly as feasible. Let’s now talk about the following likely reason for a brake fluid leak.
Always bleed your braking system after making any system fixes that involve the brake lines.
2. Breakage In the Brake Fluid Lines and Fittings
Brake lines and fittings are a further highly frequent reason for brake fluid leaks. especially the fixtures, which sometimes do not even have paint on them and can rust.
Therefore, if you reside in a place where a lot of salt is spread on the roads during the winter, you may anticipate that these fittings will rust heavily and finally stop working. Due to the fitting’s failure, brake fluid will leak and air will enter the system, resulting in inadequate vehicle braking.
To ascertain whether there is a brake fluid leak, it is frequently advisable to examine all of the lines and fittings if they have failed. Let’s now discuss the final likely reason for this issue.
3. Damaged Caliper
We wish to address a damaged brake caliper as the final factor. The actual caliper is a sizable metal object. The seals of the pistons placed on the caliper, however, are what might fail.
Your caliper may stick and develop leaks all around it if the seals on the pistons are faulty. Therefore, you should take care of this problem right now.
If your brakes are jammed and your brake caliper is seizing. It’s also very probable that the caliper itself is the source of your problem. In this instance, the caliper requires either full replacement or refurbishment.
It is frequently suggested to replace it since a rebuild kit won’t work as well as a brand-new brake caliper. Let’s now concentrate on the signs of a brake fluid leak in the next chapters.
Which are the Common Brake Fluid Leak Symptoms?
Let’s now talk about the signs of a brake fluid leak. It is frequently encouraged to be aware of the symptoms since, by doing so, you can determine whether you have the issue.
Some of the signs are obvious, while others are more subtle and need a more thorough analysis of the situation before you can identify the issue. What then are these brake fluid leak symptoms? Let’s expand.
1. The Brake Light Comes On
Probably the first and most evident indication you’ll experience is an illuminated brake light. Every time the braking system experiences a malfunction, this brake light often illuminates.
A sensor that gauges the amount of hydraulic fluid in the master cylinder whenever there are leaks is present. So, if this sensor receives any inaccurate values, the brake light symptom on the display is quite likely to occur.
When you glance at the brake light on the dash, you cannot immediately determine if you have a leak. However, if you open the brake fluid canister and find that there is not enough fluid within, you will immediately realize that there may be a leak.
Because of this, it is recommended to inspect the canister and fill off the fluid anytime there is a brake fluid leak. As soon as you can, fix the brake fluid leak as well.
2. Slippery Brake Pedal
The spongy brake pedal is another sign of a brake fluid leak. Others refer to it as a squishy brake pedal. due to the pedal’s sponge-like softness. Instead of being difficult, you should be able to stop with no effort on your part. You will have to apply more force to stop the vehicle because the brake pedal is soft.
But why is this taking place? What connection there is between the brake pedal and the fluid leak? It certainly plays a big part in it. This is true since your braking system contains air.
The air that is present in the brake system is eliminated by bleeding the system.
Yes, you read that correctly. Leaks exist, and these leaks allow air to enter the system. As a result, this air is compressed when you push the pedal. The brake pedal has a mushy sensation as a result.
This symptom is a blatant indicator that air is entering the braking system and degrading brake effectiveness. You need to fix your brake fluid leak as soon as you become aware of this issue.
3. The Master Cylinder Has Low Fluid
The level of brake fluid in the brake fluid reservoir being low is another sign of a brake fluid leak. This reservoir, which is often positioned on top of the master cylinder, is where the extra fluid is stored.
The braking fluid inside of this canister will soon run out whenever there is a leak in your system. And as soon as it runs out, air will be drawn into the master cylinder, which, as we already mentioned, would significantly reduce the master cylinder’s capacity to brake.
You may experience other signs of a brake fluid leak that are covered in this article, as well as a softening of the brake pedal. But more on the other symptoms are covered in the chapters that follow.
4. Irregular Wear On the Brake Pad
Uneven brake pad wear might also be a result of brake fluid leakage. Have you ever noticed how much more worn out the brake pads are on one side of the vehicle than the other? Why is this taking place?
Well, one of your brake system’s circuits is leaking, which is why this is happening. The master cylinder contains two circuits, in case you weren’t aware. Your car has one circuit for each side. i.e., the left side is controlled by one circuit, and the right side by another.
This was designed expressly to stop the braking system from failing. Even if one of the circuits malfunctions, the other one will still function and cause the vehicle to stop.
But there are also some dangers involved. In other words, one side of the pads will see significantly more wear and tear than the other. The pads on the side of your vehicle with working brakes are the reason since they are exerting more effort to stop your vehicle than the pads on the other side.
More effort implies that after a few thousand miles of driving in this manner, the brake pads will begin to substantially wear out. Therefore, if you see that there is a lot of pad wear material on one of the sides of the rims, it is a sign that you need to act and resolve this issue as soon as possible. Fix the brake fluid leak as soon as possible, and drive carefully.
5. When Braking, the Vehicle Pulls to the Side
The vehicle pulling to one side when braking is another sign of brake fluid leakage that frequently happens with uneven brake pad wear. Why is this the case, then? Why is the vehicle pulling to one side?
The vehicle pulls to one side because only one of the sides’ brakes is operational, which is a very easy solution. The presence of this circumstance will be greatest while braking hard. And as a result, it may put you in circumstances that might be deadly and perhaps result in your death.
Therefore, if you wish to prevent certain unintended outcomes, you must identify the brake fluid leak. We’ll go into more detail about this later in the essay.
6. Low-Stopping Power
Increased stopping distance is the final sign of a brake fluid leak that we’ll discuss. You will probably have trouble stopping if your car’s brake fluid is low.
When the brakes were functioning as they ought to from the manufacturer, the vehicle would stop as previously, but not anymore. Due to your short stopping distance, you run a much greater chance of colliding with another vehicle.
Consider the possibility of a brake fluid leak if you discover that your brakes are not up to the task and are not functioning properly. But how can a brake fluid leak be identified? In the chapters that follow, let’s go into greater detail about that.
How Does a Brake Fluid Leak Get Diagnosed?
Let’s now talk about how to identify a brake fluid leak. How can you determine if your braking system leaks? Let’s get into further detail about this subject.
It’s quite simple to identify a brake fluid leak in your car. What makes me say this? I’m stating this since this is a task that is suitable for beginners. So, how is this issue identified?
You should, however, check your stop pedal first. You need to examine the master cylinder if the brake pedal is spongy and has a lot of play between the time you push the pedal and when the car begins to stop.
The firewall is where the master cylinder is placed. The braking fluid is stored in this apparatus. Take a look inside to check the fluid’s level and condition. You have a brake fluid leak if the fluid level is noticeably low.
Additionally, check the master cylinder to see if the sides have anything oily. The master cylinder is leaking if there is something oily that is coated in dust. In such a case, go on to the brake lines and look at their routing.
See whether there are any leaks on any of the fittings by checking the fittings. If there are leaks at a certain fitting, you have located the issue. Otherwise, keep looking. Probably behind the caliper, where the brake line is attached to the caliper, is the next location you should search for. These have a reputation for forming leaks.
How Do I Repair a Brake Fluid Leak?
So how do you stop the brake fluid from leaking? This depends on what is first generating the leak.
If the master cylinder is to blame for the leak, a new master cylinder must be installed. It will be necessary to replace the brake line if it is leaking. comparable to calipers.
The calipers’ pistons frequently leak and lead to issues. The caliper needs to be either rebuilt or changed.
Finding the source of the leak is the first step in fixing a brake fluid leak. The next step is to have the problem rectified so that you may resume your regular travel once you have determined where the leak is coming from and how severe it is.
I’ll presume you’ve identified the source of the fluid by this point. Come on, let’s repair it.
Only rebuilding brake calipers, replacing braking hoses and lines, replacing the brake master cylinder, and usually bleeding are covered in this tour.
The braking system employs hydraulics. This demonstrates that the braking mechanism is run by hydraulic fluid. Hydraulic fluid is an essential component for the brakes to function properly. Without it, you won’t stop moving.
Model 1: Brake Calipers Rebuilding
Currently, brake calipers are not rebuilt by mechanics. Instead, they send it to a rebuilding facility for a thorough rebuild, and then they reinstall the caliper when the job is finished.
Instead of rebuilding the current caliper, I advise purchasing a new one. There is not much of a difference between a refurbished one and a new one. Follow these steps if you decide to rebuild and save those pennies.
Step 1: Removal of the Old Caliper
- Visit your local auto shop or dealership to purchase a rebuild kit.
- The bleeder screw bolt must be loosened. Apply penetrating oil if it’s proving difficult to work with to prevent breaking or wearing it.
- Pull the brake lines apart. Before reinstalling the caliper, check the pipes and replace them if they are worn out or cracked.
- Remove the caliper’s slider pins, springs, shims, and pads.
- Eliminate the caliper dust cover.
- Place a piece of wood slightly larger than the brake pads against the piston in the caliper.
- Push the piston out by injecting compressed air into the caliper’s inlet port.
Step 2: Fix the Pistons Again
- Use transmission fluid or another light oil to lubricate the new piston you intend to install.
- The piston should be pushed into the caliper. Remember to use the dust cover.
Step 3: Fix the Caliper Again
- Reposition the dust cover.
- The rebuild kit’s new slider pins, shims, pads, and springs should be installed again.
- Put back the brake lines in place.
- Put the bleeder bolt back in place.
- To make sure you have stopped the leak, double-check your work and put it to the test.
- By bleeding the system, the air in it is removed.
Model 2: Brake Hoses and Lines Rebuilding
There is no quick fix if the brake fluid is leaking from the hose or lines. Do it now and fix it. Additionally, carefully examine the rear wheel if the brake fluid is leaking from it. There is a chance that the brake lines, not the wheel cylinder, are the source of the leak.
The lit brake light is most likely the first and clearest warning you’ll encounter. This brake light frequently lights whenever the braking system malfunctions.
- Lift the car and use a Jack stand to support it. Take the tire off.
- The brake line should be disconnected from the master cylinder and any fittings that are close by.
- Find and eliminate all mounting brackets and clips holding the brake line.
- Take the damaged line away from the caliper.
- On the caliper, attach the new line. It hasn’t been torqued yet.
- Reattach the mounting clips and brackets to the new brake line.
- Replace the brake line’s other end where you previously disconnected it.
- Verify your work again and make sure each component is tight.
- Bleeding the system will release any trapped air.
Model 3: Wheel Cylinder Replacement
In comparison to rebuilding it, replacing a damaged brake wheel cylinder is much simpler and will give you greater peace of mind. A rebuilt cylinder and a new wheel cylinder are nearly identical.
Step 1: Remove the Wheels
- Take the hubcaps off the wheels.
- Lift the problematic wheel off the ground and use a jack stand to support it.
- Remove the tires by loosening the lug nuts.
- To make it simple to release the brake line fittings, apply penetrating oil to them.
Step 2: Take the Wheel Drum-Off
- Remove the backing plate’s dust cover.
- Using a flat-head screwdriver, tighten the adjustment for the drum brakes.
- Hammer the wheel drum in the center to loosen it from the rust.
- Take the wheel drum off.
- Take apart the brake parts If your brake shoes are drenched in brake fluid, think about buying new ones.
- Use brake cleaner to remove any debris and fluid from the surface of the drum.
Step 3: Remove the Brake Line
- Use a line wrench to loosen the brake line where it connects to the wheel drum brake fittings.
- Eliminate the brake fitting.
- To stop the fluid from leaking, get a vacuum hose ready and attach it to the brake firing.
Step 4: Put a New Brake Pot In
- Locate the bolts that are fastening the wheel cylinder and remove them.
- Remove the problematic wheel cylinder.
- By hand, thread the vacuum hose from the brake line into the new brake pot after removing it.
- As you removed the old pot, fix the new one.
- Bleed the system to release any trapped air.
Model 4: Brake Master Cylinder Replacement
Two circuits are used in more recent brake systems. Each circuit has two wheels, so if one fails, the brakes will still function on the other circuit. Both circuits receive hydraulic pressure from the brake master. Therefore, if the brake master fails, all other brake parts will also be affected.
It’s much easier and more affordable to get a new one. Both circuits will be impacted by a brake fluid leak on the master cylinder, leaving you with a flat brake pedal. The steps involved in replacing it are as follows:
If the brake caliper is locking up and your brakes are blocked. Also extremely likely to be the cause of your issue is the caliper itself. In this case, the caliper needs to be completely replaced or refurbished.
- Open the hood to locate the brake master.
- Remove the fluid reservoir lid.
- Using a turkey baster, drain the liquid. Put the recycled liquid in a secure container.
- Disconnect the electrical harness’s plug.
- By using a line wrench, loosen the brake lines.
- Remove the nuts that are securing the brake master.
- Remove the previous brake master.
- Set up the new device
- Reverse the procedure to fix the brake lines.
- Plug the wiring harness in.
- By blessing the system, remove the trapped in the air.
Model 5: Bleeding of the Brake Lines
After performing any system repairs that involve the brake lines, you should always bleed your brake system. bleeding from the brakes needs assistance.
- Recruit a helper to apply the brakes.
- While you remove the bleeder valve from the wheel cylinder or brake caliper, ask them to keep the pedal depressed. The wheels must be bled one at a time while preventing air from entering the system.
- Avoid letting the brake fluid touch your paint by catching it in a container. Paints and wax are corrosive to brake fluid.
- As your assistant presses the brake pedal a few times, lock the bleeder valve. Two or more times should be bled.
- On all wheels, repeat the process.
- Refill the reservoir of brake fluid.
- To make sure the brake system is functioning properly and smoothly, test it out.
Note: If your brake pedal is still spongy after the repair, you might want to consider bleeding all of your wheels to release the trapped air. Always replace the same component on the opposite wheel whenever you change a component on one side of a wheel.
How Much Does It Cost to Fix a Brake Fluid Leak?
The cause of the brake fluid leak plays a big role in how much it will cost to fix. Depending on the vehicle, you can anticipate spending between $250 and $600 to replace a broken master cylinder.
Simple metal fittings are inexpensive and can be purchased for a few dollars. You might need to spend a few hundred dollars on new brake lines for all of the wheels because they are custom-made.
On average, a brake caliper costs $150. But if it’s a really expensive car, this cost could increase to $600. These are the general costs associated with stopping a brake fluid leak.
We have talked about a lot of topics related to brake fluid leaks in this article. First, when the brake fluid leaks, we gained more knowledge about this issue. The brake system’s operation and component breakdown were then covered.
Following that, we talked about the causes and signs of brake fluid leaks. We became aware of every scenario. The most likely causes are faulty brake line connections or a damaged brake caliper, and the most likely symptoms are a spongy brake pedal brought on by air that entered the system.
Finally, we learned how to diagnose the issue and how much it will cost to fix it depending on its root cause.
Jim Wicks is the founder of MotorVehicleHQ. With over two decades of experience in the automotive industry and a degree in Automotive Technology, Jim is a certified car expert who has worked in various roles ranging from a mechanic, car dealership manager, to a racing car driver. He has owned more than 20 cars over the past 15 years. Ask him about any vehicle you see on the road and he can tell you the make, model and year. He loves the aesthetics of all things cars, and keeps his vehicles in pristine condition.
In his free time, Jim enjoys getting his hands dirty under the hood of a classic car or taking long drives along the country roads. His favorite car? A 1967 Shelby GT500, a true classic that, according to Jim, “represents the pure essence of American muscle.”