Why Do Brakes Squeak?


I hate the sound of squeaky brakes! All drivers will encounter squeaky brakes at some point. While squeaky brakes may be irritating, they shouldn’t be ignored.  

Why do brakes squeak? The brakes of your car can squeak for a variety of reasons. The four most common causes of brake squeaking include water settling into the rotor and creating rust, thinning brake pads, high metal content in cheaply made brake pads, or failure to lubricate the back portion of the brakes. 

Throughout the time you have been driving, you might have noticed a squealing noise from your brakes at one point or another. This can become quite annoying if the problem persists, and can also be worrisome if you are unsure why it is happening. 

If you are experiencing squeaks coming form the brakes of your car or have ever been curious about what makes this happen, the information in this article will give you the answers to all of your questions. Keep reading to find out why the brakes on your car might be squeaking. 

Why Do Brakes Squeak?

When it comes to squeaking brakes in a car, there are so many individual things that could cause them. From weather conditions to improper maintenance, the possibilities of why your brakes are squeaking could make you scratch your head. 

However, there are a few common reasons why the brakes in your car might be squeaking. In this section, we will be specifically highlighting 4 of the most frequently occurring causes of brake squeaking in any car. 

Common Causes Of Brake Squeaking :

  • Morning squeaks 
  • Thinning brake pads 
  • Brake pads have high metal content
  • Lubrication needed 

One of the most common causes of brake squeaking in cars is a collection of moisture form sitting overnight. When there is rain or any kind of condensation present within the brakes, there will be a new layer of rust that forms on top of the rotor. 

When you turn your car on and use your brakes, the rotor will turn itself automatically. As this is happening, the brake pads will begin to scrape this layer of rust off of the surface of the rotor, with the excess materials getting caught on the outer edge. 

The tiny pieces of rust travel into the leading edge of the brake pad, which ultimately causes the squeaking noise to be released form your brakes when you push on the pedal. 

The next common reason why your brakes would be squeaking is due to thinning brake pads. When your brake pads are collecting wear and tear after normal use, they will gradually become thinner as a result. 

When the brake pads become too thin, the brake-wear indicator will cause the squeaking noise to let you know that it is time to replace them. 

Brake-wear indicators are usually fashioned in the form of steel tabs that are connected to the back of the brake pad. They will hit the rotor when the brake pad shows signs of significant wear in order to notify the driver as soon as it is detected. 

When brake pads are used within an automobile, they are usually made with some traces of metal pieces. However, if you opt for the low-cost options when it comes to brake pads, yours will likely have much higher metal content that will eventually start to scrape against the brake pad itself. 

When you are pushing on the brake pedal and the metal is creating friction against the brake pad, it will create a long squeak from the inside of the car. 

Aside from the inner components of your brakes coming in close contact with each other, the last common reason for brake squeaking is the need for lubrication. 

If you are experiencing a lot of squeaking from the back of the car, in particular, you will be able to identify a problem with the shoe-to-backing-plate contact points. When these components are not properly lubricated, they can make loud noises every time you try to put your brakes to use. 

How Do Brake Systems Work?

When it comes to understanding how brake systems work in motor vehicles, it is important to note that there are two common types of brakes: disk and drum brakes. While most of the cars that you will see on the road in the current day contain disk brakes on all four wheels, you might still come across a vehicle with the latter. 

In this section, we will be briefly discussing how both brake systems work inside an automobile, with a description of each in the list down below.  

How Disk Brakes Work:

  1. Brake fluid located in master cylinder 
  2. Fluid moves into caliper (against piston) 
  3. Two brake pads are squeezed against the rotor (by the piston) 
  4. Attachment to the wheel makes the vehicle stop 

How Drum Brakes Work:

  • Brake fluid moves into cylinder of the wheel 
  • Cylinder pushes out brake shoes 
  • Friction linings put pressure on the drum 
  • Attachment to the wheel makes the vehicle stop 

As you can see, both of these braking systems follow through with a similar pattern to stop the wheels of a vehicle, only one is located on all four wheels while the other focuses on the back. 

Despite the differences throughout this process, the basic functions of any braking system include brake fluid moving through one component, with other actions in between until the wheels of the car finally come to a complete stop. 

With a basic idea of how these systems normally work, it will be easier to understand why the previously discussed events would disturb these processes, causing the brakes to squeak. 

Keep reading to the next section to learn how you can prevent the brakes in your own car from squeaking. 

How To Prevent Brake Squeaking 

Now that you have found out almost everything that you needed to know about why brakes squeak and some of the potential causes, you might be wondering how you can stop and prevent it. 

After all, this is why you searched this question on the internet, right? In this section, we will be going over how you can stop brake squeaking in your car before it even starts at all. 

How To Prevent Brake Squeaking:

  • Keep your car in a dry place overnight 
  • Make sure contact points are lubricated 

First and foremost, you should always makes rue that your car is being stored in a clean and dry place, especially when you are leaving it overnight. 

In order to prevent rusting and squeaking from moisture that gets into the rotor of the brakes, you will need to make sure that no water can even get into this area. 

In addition, you will want to make sure that all of the contact points toward the back of the car are properly lubricated at all times. If you are on top of this task on a regular basis, you will not have to wait until you hear those dreaded squeaking noises before you apply the proper materials to these areas. 

As you can see, there are plenty of common causes for why the brakes in your car could possibly be squeaking. With a basic understanding of why you are experiencing these effects as well as how you might be able to fix them, you should not have to worry about squeaky brakes at any time in the future. 

Arwood

I'm Arwood, but the grandkids call me Big Papa. After retiring from teaching automotive classes for 30+ years I decided to create a blog about all the questions I used to get about brakes and anything automotive.

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