What Are The Symptoms Of Low Brake Fluid?

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Having a brake failure can be frustrating, especially when you need to slow down or stop your car. There are a lot of things that can be responsible for this to happen.

One of these is low brake fluid. But what are the symptoms of low brake level?

Providing answers to this question is the reason why I am here again. Let me reiterate that learning the symptoms of low brake fluid is as equally important as knowing the causes. After all, the cause gives birth to the symptom.

What Are The Symptoms Of Low Brake Fluid?

The symptoms of low brake fluid in your automobile include:

  • Spongy pedal-foot feel
  • Extended stopping time
  • The brake warning light illuminates

The brake fluid forms one of the most crucial needs of your car’s braking system. Your automobile brakes can have all the components and accessories. Without the brake fluid, the brakes won’t perform as they should.

Just as the motor oil and power steering oil serve as lubricants, the brake fluid comes in handy to lubricate the moving metal parts of the braking system. The coolant and the lube oil also play the same role.

Specifically, the fluid moves throughout the brakes, starting from the brake lines. This presence of the brake fluid prevents any form of corrosion or rust from getting to the brake rotors, wheel hub, and brake calipers.

However, when the fluid level is low, the above symptoms – which I shall discuss in detail later – show up. You shouldn’t allow these signs to linger. Their neglect could pose a serious threat to the overall performance of your vehicle brakes.

In the end, the malfunction of the brakes threatens your safety on the road. First off, let’s examine what the brake fluid is and how it works in the network of your car’s braking system.

Brake Fluid And How It Works

Typically, brake fluid, also called hydraulic fluid, is a kind of fluid that you pressurize and pour into the system of the hydraulic brakes of your automobile. Featuring a yellow spectrum or other hues of color, brake fluid comes either in the form of polyethylene glycol or silicone.

The polyethylene glycol-based brake fluid includes DOT 5.1, DOT 4, and DOT 3. They are great absorbent of atmospheric moisture and highly compressible.

The silicone-based brake fluid, on the other hand, comes with higher viscosity index when used under high temperature or heat. Besides, they are more stable and can produce an incredible braking feel.

How does brake fluid work in your automobile hydraulic system? The mode of operation of the brake fluid is pretty simple.

Have you ever imagined how the brain works with electrical impulses to spur the muscles to action? The mechanism of the brake fluid is similar to this. For instance, when the brain neurons receive electrical impulses from various cells, they send the signals to the brain.

In the same manner, when you hit the brake pedal, the brake fluid speeds through the brake rotors and calipers. From there, it sends the signals to the braking system to slow down or stop your car.

When you step on the brake pedal, the brake fluid runs through the brake calipers to give off some braking pressure. The pressure passes through the master cylinder and electronically and mechanically pushes a piston.

The calipers in turn press the brake pads to make the brake rotors act. When the pads clamp down on the rotors, they create friction which causes the car to slow down or stop. It’s that simple.

Spongy Pedal-Foot Feel

The first culprit for a spongy brake pedal feel is a low level of brake fluid. Once the brake fluid is out, the brake pedal gives off a springy feel. The pedal may also go to the floor.

Typically, your brake pedal should be firm against the foot when you hit it. The firmness will enable the brakes to feel solid and allow your car to stop and slow down.

There are other reasons your foot may experience this soft pedal feel. For instance, if there’s air in the brake lines or the flex is leaking or bad.

Leaking disc brake calipers, worn master cylinders, poor rear brake pads, and ABS hydraulic assembly malfunction may also be responsible for a squishy foot-pedal contact.

Extended Stopping Time

When you hit your foot on the brake pedal, the car should come to a gradual halt. This period between hitting the pedal and the car coming to a stop should be pretty short.

When the brakes are running on low brake fluid, the time the car will take to stop will extend beyond normal. In fairness, the speed at which you’re driving determines the stopping distance and time.

On average, if your car is speeding at 20 miles per hour (mph) and you hit the brake pedal, the car might travel another 20 feet before it will completely come to a stop.

However, if the car is running on low hydraulic fluid, the time will delay, causing the car to travel up to 30 feet or more.

The other factor is the condition under which your car is operating. Worn tires, poor weather, icy roads, or bad brake parts are culprits.

Illuminating Brake Warning Light

One of the earliest signs of a low level of brake fluid is that your brake warning light will come on. By simply looking through your dashboard, you’ll notice that the warning light will illuminate.

The braking system features the brake tubes and brake lines where the hydraulic fluid fills up. One end of the system consists of the master cylinder while the other end comprises the brake calipers.

When you press down on the brake pedal, the cylinder is actuated and so pressurizes the hydraulic fluid filling the brake lines.

On the master cylinder is a sensor that senses and signals a faulty system in the braking system. This sensor receives a signal from the master cylinders indicating that the hydraulic fluid is low.

When this happens, the brake warning light will come on. It’s worth mentioning that the brake warning light can also illuminate if you engage the parking brake.


What Are Other Symptoms Of Low Brake Fluid?

Another symptom that comes with low brake fluid is discolored or dirty fluid. The hydraulic fluid will become dirty and lose its original amber, yellow, or clear blue color once it’s reduced in quantity.

Once you notice that your car’s hydraulic fluid is appearing contaminated or discolored, you should check the fluid level. It may have gone low.

How Can I Fix Low Brake Fluid?

Remedying low hydraulic fluid is straightforward. The first thing to do is to study the signs and ascertain that they are symptomatic of the suspected cause.

Remember I said earlier that some of the symptoms could result from other mechanical sources or electrical causes. Once you’re sure that the symptoms are truly due to low brake fluid, it’s time to take the following steps.

The best and first thing is to do a brake fluid flush. Here’s a simple step-by-step guide to doing a brake fluid flush.

A beginner Do-It-Yourselfer will complete the process within minutes. You can also follow your vehicle’s manufacturer’s recommendations.

  1. Place a container under the car
  2. Connect a hose to one end of the brake valve
  3. Direct the other mouth of the tube towards the container
  4. Ask a friend to pump and hold down the brake pedal
  5. From your end, pop open the brake valve
  6. The old fluid will start to come out and empty into the container
  7. Replace with new, clean, and fresh hydraulic fluid

Alternatively, you can always prevent low brake fluid by ensuring regular inspection of the vehicle. Your car’s braking system needs special attention and check.

But brakes can get dirty with time. Air and moisture are core enemies that can contaminate your brake fluid.

What Are The Causes Of Low Brake Fluids?

As you may have noted throughout the article, a few things can be responsible for low brake fluid. They include:

  • Air or moisture-filled brake lines
  • Leaking
  • Worn brake pads
  • Warped brake rotors
  • Leak in the braking system
  • Faulty brake cylinder
  • Extreme heat in the brakes

Can I Drive With Low Brake Fluid?

No, you can’t and shouldn’t drive when you’re running on low brake fluid. In fact, if any part of your car braking system is faulty or low on performance, the best thing to do is to pull over and inspect.

The good thing is that it won’t take you time to fish out the culprits. Replacing the brake lines, the brake pads, or the brake rotors isn’t rocket science, as well.

Final Word

With the explanation above, answering the question, ‘what are the symptoms of low brake fluid’ should be a walk in the park.

When the brake fluid sends pressure through the brake pedal to the wheel hub, your car wheels are clipped. This will slow down or stop the vehicle. This can only happen if the fluid is at the normal gauge.

However, once it becomes low, what you see is that when you press down on the brake pedal, the car won’t stop. The slowing down process will also be extremely slow.

You need the fluid to help to augment the pressure that your foot receives as it makes contact with the brake lever. I’m not sure any mechanic will emphasise car safety outside the health of the car.