What Does Brake Fluid Smell Like?

Brake fluid is extremely important in your car’s braking system. If it leaks, your brakes will start to fail. But what does brake fluid smell like? How do I detect a brake fluid leak in my car? This article will answer all such questions.

Sometimes you might notice a puddle of liquid on your garage floor, under the car’s bonnet. Your vehicle uses different fluids to function. In most cases, a leak in your car’s fluids is harmless. You can fix it with little effort. 

Sometimes, however, a leak in car fluids can be dangerous and may require immediate attention. You need to first identify the liquid that has fallen on the ground. 

Diagnosing leaks from your car is not tough. The color, smell, location, and consistency will help you detect the leaks. For example, new brake fluid is usually yellow but looks brown if it has been in the car for some time. 

What Does Brake Fluid Smell Like

But what is the smell of brake fluid? Have you ever used fish oil at home? That’s what it smells like. You can also put a couple of fingers in brake oil to check how smooth or slippery it is. It is usually more slippery than transmission fluid or steering fluid.

If the brake fluid is draining from your car, you can check the brake fluid reservoir and you will find the level to be low. At the same time, you will also notice that your brake pedal is spongy while driving. This indicates that the brake is not functioning effectively due to low brake fluid.

Brake fluid leakage is quite dangerous and should not be taken for granted. Kindly do not drive your car anywhere except your nearby garage at the earliest. They will inspect and repair your vehicle. Let’s discuss more brake fluid, why it leaks, how to identify the leak and what brake fluid smell like under different circumstances.

Also read: What kind of brake fluid is used in Harley Davidson bikes?

What Is Brake Fluid?

Brake fluid plays a vital role in the braking system of your vehicle. It is usually stored in the reservoir. Whenever you press the brake pedal, the brake fluid flows from the reservoir through to the master cylinder and is compressed to high pressure. 

The pressurized brake fluid flows through the brake lines and moves towards the caliper. It exerts a force on the pistons of the caliper. As a result, the brake pads attached with pistons come in contact with the disc or rotor and stop your vehicle.

You might like to read: Why Is My Brake Fluid Green?

General Features Of Brake Fluid

#1. High Boiling point

The brake fluid is subjected to high temperature in disk and drum braking systems. So brake fluid should have a very high boiling point so that it will not vaporize from the brake lines.

#2. Hygroscopic

Brake fluids used in most vehicles are glycol ether-based. The glycol ether-based brake fluids are hygroscopic, which means they absorb moisture from the air when they are put in the hydraulic braking system. 

Brake fluid absorbs moisture from the microscopic pores in hoses, brake lines, and others. This is what causes brake fluid to develop air bubbles and why you need to bleed your brake fluid every now and then.

What Does Brake Fluid Smell Like

#3. Noncorrosive

The brake fluid used in your vehicle should be noncorrosive. If it were to start corroding the metallic and rubber parts of your car, it would destroy your brakes.

#4. Constant Viscosity

The term viscosity refers to the thickness of the brake fluid. The brake fluid should have constant viscosity under a wide range of temperatures.

You might like to read: What Happens If You Overfill Brake Fluid? 12 Reasons Not To Do It

5 Reasons Why Brake Fluid Leaks From Your Vehicle

There are many potential reasons why brake fluid from a car can leak from your vehicle. I am discussing some of them below.

#1. Damaged Brake Lines

The brake lines are designed to withstand harsh weather and different weather conditions. However, it may get damaged because of bumps or accidents or may rust with time. 

Broken brake lines can lead to leakage of brake fluid

#2. Worn Seals In The Calliper

The rubber seals in the caliper get damaged with time, which causes your brake fluid to escape, causing a leak.

#3. A Faulty Master Cylinder

The master cylinder is the heart of the braking system. It has valves and seals which can wear out with time. Consequently, it can lead to leakage of brake fluid.

What Does Brake Fluid Smell Like


#4. Damaged Brake pads

Brake pads are another essential part of the disc braking system. Brake pads consist of steel plates with friction lining on their surface. Over time, brake pads wear out and become thinner. 

But when it gets too thin or damaged, the caliper pistons become hyperextended, damaging the seals and leaking brake fluid (see point no. 2 above).

#5. Damaged Brake Fluid Reservoir In Master Cylinder

The brake fluid reservoir in the master cylinder is made of plastic. It may get damaged because of excess heat exposure, which leads to brake fluid leakage.

You might like to read: What Happens When You Run Out Of Brake Fluid?

How do I know if I am leaking brake fluid? 3 Ways You Can Check

#1. Flashing Of Brake Warning Light

When the brake warning light flashes then, it indicates various things. I am listing them below.

  • Your parking brake is engaged
  • There is a low level of brake fluid in the reservoir
  • Defective sensors
  • The problem in the antilock braking system

The best thing is to take your car to the nearest mechanic as there are so many reasons for flashing brake lights.

#2. You, Will, See a Puddle Of Fluid Below Your Car

You will find a puddle of fluid below your car. If the fluid is yellow to dark brown and has a fishy smell, it indicates brake fluid.

If your car is leaking brake fluid, then the location of the puddle will tell you which brake component is causing leakage. 

For instance, if you see a puddle of brake fluid in the center or rear of your car, there is a problem either in the master cylinder or brake lines. If you find a puddle of brake fluid near the wheels, it indicates there is a fault in brake calipers.

What Does Brake Fluid Smell Like

#3. Your Brake Pedal Sinks To Floor

When there is brake fluid leakage, then the brake pedal of your vehicle will be spongy, or it will sink to the floor. If this happens to you, I will strongly advise you to stop driving and take your car to the nearest mechanic.

You might like to read: Brake Fluid Pressure Is Measured In What Unit?

Does Brake Fluid Smell Like Burnt Rubber?

Yes, brake fluid may sometime smell like burnt rubber. I have discussed some of the possible reasons brake fluid may smell like burning rubber.

#1. New Brake Pads

New brake pads are coated with resin. If you are using it for the first time, then it can produce a burning smell. However, the smell goes away after a few days.

#2. Overworked Brakes

When you use hard brakes for a long time, the heat starts building up, which causes the brake fluid to boil, and finally, you smell something burning.

#3. Worn Out Brake Pads Or Rotors

The brake pads or rotors are a vital part of the disc braking system. They help in dissipating the heat generated in your vehicle. But as you use these components for a long time, their ability to lose heat reduces. Consequently, it will cause excess heat, which can boil the brake fluid. The aged brake fluid converts into compressible gas, which results in a burning smell.

#4. Is Brake fluid odorless?

No brake fluid is not odorless. New brake fluid is usually yellow but can get brown with time. It is oily in touch and has a fishy smell.

You might like to read: No Brake Fluid To Rear Brakes When Bleeding: 6 Reasons Why This Happens

A few Final Words

The brakes of your car will not work without brake fluid. So there should be sufficient brake fluid in the reservoir so that your car will stop comfortably and at your desired location.

If you find puddles of liquid under your car and discover it has brake fluid, then take your vehicle immediately to the mechanic.Thank yuo for reading, we hope we answerd most of your questions. If we left something out, write to us in the comments below and we will revert back to you.

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Sean Mendez

Hi, I am Sean, a self-confessed petrolhead. I live in Boise, Idaho with a busy family of four and our energetic Labrador retriever. Thank you for visiting my website. You can find my email on the contact page.

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