How To Adjust If The Drum Brake Self-Adjuster Not Working?

By: Saiful Islam | July 15, 2022

Self-adjuster is a very component of the brake system, it ensures that the brake shoe is closer to the drum and helps in maintaining a consistent pedal feel and response. 

Is Your Drum Brake Self-Adjuster Not Working? Well, if your wheel is locking up or your car is braking unconditionally, it indicates there is some serious issue in the drum brake self-adjuster of your vehicle. 

Therefore, if there is any problem with the self-adjuster then it can have a serious impact on the star wheel alignment and the entire brake system of the car. So, this article is all about adjusting your drum brake self-adjuster easily in just 10 minutes by yourself.

What Are The Most Common Reasons For The  Drum Brake Self-Adjuster Not Working?

The self-adjuster is the vital component of the entire drum brake mechanism. If your drum brake self-adjuster fails, there could be several reasons. The following section explains all the possible reasons responsible for the drum brake self-adjuster failure:

Rusting Of The Self-Adjuster Material

The drum brake self-adjuster is made up of cast iron material, which has corrosive properties, leading to the rusting of the self-adjuster material, gradually. It might be possible that the wheels of your vehicle were exposed to stagnant water for days. 

The chemical properties of iron are such that it becomes rusty as it comes in contact with air and water, limiting its durability. The shoes then sit too far from the drum, which results in reduced stopping capability of your vehicle. 

The Self-Adjuster Arm And The Gear Are Not Aligned

The drum brake self-adjuster is a small but very vital component, responsible for altering the function of the shoes in the drum as the lining wears out, automatically. Sometimes the adjuster is unable to adjust back to its position and loses the alignment with the gear. 

Most likely the gear and adjuster arm will not fit in their places and no clicking sound can be heard. This situation causes serious brake issues in your vehicle and could prove to be life-threatening, as it could lead to serious accidents.

Worn Out Self-Adjuster

Due to the extensive use of the vehicle, the components of the drum brake, especially the self-adjuster, tend to wear out. Excessive use causes the wear and tear of the self-adjuster or the adjusting screw. This could lead to loose parking brakes, a low pedal, and reduced stopping power. The only option left after determining the self-adjuster problem is replacing the self-adjuster.

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How To Detect Brake Drum Self-Adjuster Problems?

You might feel the difference in your brake pedal as you use your brakes to stop the car. As you step on your brake more times every day than you realize, continued usage can wear the brake system components down. If you feel a strange sensation coming from the brake pad when you depress it, it indicates that your drum brakes have some problem. 

Usually, the brake pedal will shake, but it can also feel as if it is pulsing or vibrating. Your worn-down drum brake shoe needs to be changed before it becomes more difficult to stop your car. So, you have to notice these signs either through touch or through sound.

Brake Drum Self-Adjusters Importance                                                                  

Drum brakes consist of the return springs to return the shoes to a rest position and hardware to fit the shoes to the backing plate. The shoes return to a complete rest position when the pressure to the wheel cylinder is released.

Sometimes, the master cylinder may possess residual check valves to control air from being removed beyond the wheel cylinder cup seals when the shoes are drawn back by the return springs. 

Therefore, it is better to replace the clips, springs, self-adjuster, and other parts along with the brake shoes. Additionally, the pressurized wheel cylinders may cause a delay in drum brake applications. For the shoe to push the brake drum, it needs to overpower the force from the return springs.

Self-Adjuster Examination                      

As the secondary shoe glides off the anchor pin each time, it will result in an adjuster lever and the notched wheel staying in contact while moving in opposite directions. A cast-iron groove can wear off in the lever so is the angular wheel. This can cause a problem with the star wheel. The adjuster lever containing a cast-iron groove may hinder the self-adjuster from better functioning. 

However, in a disc/drum application, the automatic self-adjusters play a vital role in keeping appropriate brake balance when the shoes are seated to the drum. Thus, it significantly involves the adjuster wheel, in the starting miles. The self-adjuster will hold the brake pedal at its accurate height. 

Solving Drum Brake Self-Adjuster Problems:

In order for the smooth working of your brake system, you can solve your drum brake self-adjuster problems in the following ways:

What To Do If The Self-Adjuster Is Not Clicking?

If the gear and the adjuster arm of the self-adjuster are not clicking, it is a clear indication that the self-adjuster has worn down. Do you hear a scratching sound while braking? Another significant sign of the drum brake self-adjuster problem is the sound when your car slows down and stops. 

The rasping or scratching sounds while you brake, then your drum brakes self-adjuster have worn down too far, and the gear and the arm of the self-adjuster are not in place. 

As far as disc brakes are concerned, you will hear a grinding sound when the brake pads, self-adjuster, brake adjuster, or rear shoe have worn down. Irrespective of the sound you hear, have your brakes examined and the worn parts replaced before it becomes tougher to stop your vehicle. Replacement is the only option you have in this case.

How To Fix The Self-Adjuster By Yourself?

When you face problems like the drum brake self-adjuster not working,  and needing some manual adjustment then, you should want to jack up one side of your car to be the side that you are adjusting off the ground, so you can feel the resistance in the tire or the wheel whenever you try to spin it. 

There is a little rubber piece right on the back of your wheel or tire. So you go behind the wheel, try to remove the little rubber piece, and use a flat head screwdriver. Removing this rubber piece will open the hole for your screwdriver to go inside. As your screwdriver goes inside and you reach the self-adjusters.

Tightening is by pointing the backhand of your screwdriver up (the tip of the screwdriver goes from top to the bottom). You will hear the clicking sound. The small gear locks the adjuster accurately every time the self-adjuster clicks. 

The turning of the self-adjuster will push brake shoes out and squeeze down on the brake drums or the rear drum brake, which is going to tighten the star wheel.

Resetting The Drum Brake Self-Adjuster

Also, the installation of brake shoes requires resetting the self-adjuster. So, those shoes create a good connection with the inside of the drum. This procedure may require some time and training but results in a brake pedal that feels as strong as a rock. 

Sometimes cleaning and adjusting the brake drum feels as; if you have replaced the complete brake system. Replacing the shoes of your brakes takes time to set the brakes correctly. It will make your brakes feel better, and your parking brake will also function better.

Hardware Tool Kit To Replace The Self-Adjuster

The self-adjuster often comes in a proper tool kit called a hardware tool kit and is not very expensive. It requires a bit of training to replace the drum brake self-adjuster correctly. Do not tighten it too much as tightening too many causes the brakes to pull and overheat, resulting in other problems. Also, if you are replacing your brake shoes, think about replacing the self-adjuster and other components. 

Breaking-In Self-Adjusting Electric Brakes 

The process to break-in self-adjusting electric brakes mostly requires an initial calibration. Then, the brakes will continue to position themselves to the appropriate tightness as you power them while towing. 

As a general rule for getting to the maximum braking power, it takes nearly 200 miles of usage for self-adjusting assemblies. How to speed up the process of self-adjusting brakes to break-in? Take your vehicle out to an empty parking lot and use the manual override on the brake control many times as you drive at a slow speed. This process should make brakes tighter and tighter with each application.

Brake Drum Self -Adjuster Mechanism

The material used to make a brake drum is cast iron which is a good conductor of heat, and the drum provides friction when the brakes are applied. The backing plate of the drum brake plate has all the essential instruments and houses all the components. The first component is the brake shoe. Brake shoes are produced from frictional material or brake lining and consist of a steel frame. 

The material is attached to the outer side of the brake shoe frame. The next component is the wheel cylinder. A wheel cylinder is connected to the hydraulic system, containing brake fluid pistons that move outwards when pressing the brake pedal. Shoe retaining clips hold the brake shoe in place. 

A spring is attached to the shoe, which lowers the hydraulic pressure when the brake pedal is released, causing the springs to remove the cylinder piston resulting in the brake shoe drawing away from the drum. Thus, causing the wheel to spin freely once more.

How Does The Drum Brake Self-Adjuster Work?

The drum brake uses the self-adjusting tool adjuster to take up the extreme clearance created as the friction material on the brake shoe worn down decreases, the return motion of the shoe. 

It confirms that the brake shoe is closer to the drum and maintains a smooth pedal feel and response. Finally, we have the hand brake mechanism. The cable enters the drum through the backing plate. It connects to the adjuster cables on the brake shoe lever that works by activating the rear brakes and the rear brake shoe. 

The parking brake cable has one parking brake lever attached to the secondary shoe of the drum. The force from the spring pulls the adjuster cable on the arm. The drum shoes expand to the drum, and the wheel will stop automatically.

Answers To Your FAQS:

What Does Self-Adjuster Do To Adjust Itself?

The adjuster rotates in a way that clicking sound could be heard, finally fixing itself in the position again. This movement which is voluntary as the brake pedal is released causes the self-adjuster to adjust and come back to its position. Every time the brakes are applied the adjuster moves and then itself adjusts.

How Does The Self-Adjuster Work?

The shoes inside the drums press against them when you step on the brake pedal. Self-adjuster takes up the extreme clearance created as the friction material gathers on the brake shoe to prevent it from wearing down. Therefore, a self-adjuster plays a significant role in keeping your car brake accurate.

Can I Myself Adjust The Self-Adjuster?

You do not need any particular skills to be able to adjust the adjuster by yourself, make sure your car is in parking mode, the pressure generated slows down the wheels. There is a little rubber piece right on the back of your wheel or tire. So you go behind the wheel, try to remove the little rubber piece, use a flat head screwdriver, and adjust accurately.

How To Ensure Perfect Brake Application After Replacing Drum Brake Self-Adjuster?

Once you have replaced your drum brake self-adjuster, your vehicle will brake at perfect timing provided that the adjuster is installed correctly. After the shoes have been seated in the correct position, the self-adjuster will shift the angular wheel. Substituting the self-adjusters can assure perfect brake application and height of the pedal.

What Is The Role Of The Rear Drum Brake Self-Adjuster?

The rear drum brake self-adjuster helps in stopping the rear wheels, it also helps when the parking brake or the emergency brake (e brake) is set, compressing the park brake shoes against the rear drum. 


The drum brake self-adjuster is a minute but integral part of your brake system. If your self-adjuster has become rusty, it indicates that the self-adjuster of your car has worn down. 

The self-adjuster mechanism is of significant importance in the drum brake, as it ensures a smooth pedal feel. Thus, if a problem like a drum brake self-adjuster not working arises, adjust it manually or take your car to an expert to do it for you.