Are Drum Brakes Self Adjusting?

This post contains affiliate links. Read the full disclosure here.

A drum brake is a kind of vehicle in which brakes shoes are forced against the smooth internal surface of a drum mounted on a rotating wheel.

Generally, a drum brake uses friction with the aid of brake shoes or pads to press against the internal surface of a cylinder commonly referred to as a brake drum.

In summary, it is terminology that refers to a brake mechanism in which brake shoes press against the inner surface of the brake drum.

It is known that disc brakes are a lot more effective and reliable compared to all other types of brakes, which are provided in most modern cars. Do drum brakes self-adjust? We shall see about this question soon enough.

Most drum brakes are equipped with a self-adjuster mechanism. This is because the internal surface of the drum gets worn out progressively, while the brake shoes also wear down.

The piston will need more brake fluid to travel the extra distance created by this wear and the brake pedal will have to go farther down if it is pressed before the brake can be effective.

It is for this reason that most drum brakes are fitted with a self-adjuster.

Therefore, yes, brake drums are self-adjusting as a means of countering wear in both the brake shoes and the drum.

A sort of modicum of self-adjustment is also fitted into the drum brake system. However, this self-adjusting mechanism only works whenever the vehicle is driven backward and also only when you are using the parking brake as well.

In the situation of driving in reverse, if you press the brake pedal, the brake shoes will expand in response to that.

Trending Searches

Table Of Contents

How can you tell when a drum brake is self-adjusting?

To tell with any certainty whether a brake drum is self-adjusting or not, there are certain things you should look out for.

Essentially, you would be able to identify a drum brake by the placement of the self-adjuster or anchor pin. Similarly, the position of the self-adjuster is at the bottom in between the primary and secondary brake shoes.

Along the same line, the anchor pin can be located at the top between the double brake shoes. These self-adjusting brake drums utilize a kind of adjusting screw and notched wheel, which levers much like the Bendix/Wagner equipment.

In this case, a lever is fixed to one of the brake shoes to adjust the notched wheel. And on the adjusting screw, there is not any pressure even when the brakes are being applied, thus enabling the lever to rotate the notched wheel all by itself.

In the case of a trailer, for instance, you can tell whether there is a self-adjusting unit by simply pulling on the hub or drum off the trailer spindle and checking for a kind of adjustable bolt that would commonly extend across the brake assembly itself.

How can I make my drum brake self-adjust?

Making your brake self-adjust is very easy provided you know how to go about the entire process. The following steps will help you out.

Step 1

Firstly, to make your brake self-adjust, jack up the car and suspend its rear wheels after parking it safely and engaging the parking brakes.

This is done by locating its jacking point next to the rear wheels and placing your jack to lift it on one side from the ground.  You can utilize a jack stand to maintain it in one place. Repeat this procedure for all the other rear sides of the wheel.

Step 2

This step involves removing the wheels. After lighting the vehicle, make sure to remove its tires. Next, unbolt its lug nuts gently from the wheels.

In this process, you should make sure to keep the nuts in a safe place to easily get them back when you are done.

Step 3

Thereafter, you should locate the drum brake adjuster which is commonly at the rear base of the brake drum before removing the dust cover on it with a flat screwdriver.

Then, turn the brake adjuster clockwise or anti-clockwise to enable you to feel exactly where you have to turn it to. Note that most brake adjustment directions are clockwise. In applying the screwdriver downwards, the brake adjuster is supposed to move upward to bring the brake shoes close to the drum.

Make sure that there is not much drag to allow for the easy stoppage. Should the drag be too much, the brake may not operate as expected.

As long as the tire can spin with a little drag and not freely or forcefully, you will have to do the same with the other wheels too. Next, you should drag the hand brake lever to see exactly how it is. Should it be too free, you would have to add more adjustments.

Step 4

The moment you have adjusted the brake satisfactorily, you should reinstall the dust cover to its right place. Then, confirm whether everything is properly in place.

Step 5

This is where you should reinstall the tires you removed before. After that, make sure to tighten up the lug nuts with the aid of a ratchet and socket or even wheel spanners until they snugly fit.

Step 6

This step involves lowering the car. To do this, you should put your jack on the correct jacking spot before raising the car to enable you to remove the jack stand.

Then, you should lower the vehicle and do the same on the wheels of the other side as well.

Step 7

You should pump the brake pedal a couple of times before you drive the vehicle.

Finally, drive the car to a safe location and ascertain whether your brakes are functioning as expected. If they are doing well, everything is confirmed to be alright.

How long does it take the drum brake to self-adjust?

Generally speaking, it should not take more than about 200 miles of driving before your self-adjusting brakes get to their best levels of braking power.

To hasten up the whole process, you should take your trailer out to a free space and apply its manual override on the brake controller a few times while you drive slowly.

How do I know if my drum brake needs to be self-adjusted?

To know whether your drum brakes need any adjustment, it requires about 2 inches of travel. Therefore, if you are already at the 2-inch limit, it is a confirmation that your brake drum needs adjustment.

Regular adjustment of the drum brakes ensures that your brakes do not drag when driving since that is capable of robbing power from the vehicle and also causing your brakes to wear out much more quickly.

Usually, drum brakes need to be adjusted whenever you observe that the brake pedal has to be forced down very far before the brakes become effective in slowing down the car.

Generally, most brake drums need adjustment at least once after traveling about 10, 000 miles or even less than that before thinking of any replacement.

What happens if I stop the drum brake from self-adjusting?

If you prevent your brake from self-adjusting, you are liable to deny yourself maintaining a proper brake balance whenever its brake shoes are seated to the drum.

Also, the linings on the premium replacement shoes are eccentrically ground just so as to produce a clearance at the heel of the shoes and its toe.

What is the essence of the self-adjusting drum brake to the car?

The importance of the brake drum adjuster is simply to assist in maintaining a proper balance whenever the brake shoes are seated to the drum.

For this purpose, the linings on the premium replacement shoes are somewhat eccentrically ground to provide clearance at the heels of the shots and their toes.

All self-adjusting brake drums adjust on their own and are also self-centering as well. Therefore, whenever they are applied, the brake caliper will move to the center from either of the sides.

Are Drum Brakes Self Adjusting – Conclusion

Self-adjusting brake drums are a sort of automatic drums that adjust themselves as a means of maintaining the most appropriate function and effectiveness of the braking system of a vehicle.

  It is easy to tell whether or not your vehicle is fitted with this device. Fortunately, you can determine how well they function through equally very simple procedures.

This is of paramount importance after knowing the relevance of brakes in a  vehicle. To ensure that your brakes function properly, you should inspect them regularly and attend to any problems promptly.

This is necessary since the brakes ensure your safety as well as the safety of all other people on the road.

If any information you require is not in the user manual, you can consult the manufacturers or experts in the field. After all, we can never be too careful, or can we?

Leave a Reply