What Are Wheel Cylinders? (All You Need To Know)

Your car’s brakes are perhaps one of the essential systems on the vehicle. After all, if the brakes fail, things can become very dangerous very quickly.

The modern braking system is quite complicated with many different parts, including the wheel cylinders. While this part is a bit obscure, they are necessary for the overall functioning of the brake. For more information on what wheel cylinders are and how they work, keep reading below.

What Are Wheel Cylinders?

The wheel cylinder is only one part of a car’s braking system. When working properly, this piece puts pressure on the brake shoes when you press down on the pedal. In turn, the brake shoes press against the drum and slow down the vehicle. With normal wear, these cylinders can sometimes end up with a leak, which can be dangerous.

For information on how wheel cylinders work and what to do if they develop a problem, read the FAQ below.

What are the Wheel Cylinders Used For?

The wheel cylinder is part of the drum brake. In a working brake system, the wheel cylinder will put pressure on the brake shoes when the brake is activated. In turn, this presses against the drum, slowing down the vehicle.

As you might suggest, the modern braking system has a lot of moving parts, and the wheel cylinder is only one of them.

However, they are essential to the braking system. Without them, the brakes would not work properly.

What Happens When a Wheel Cylinder Goes Bad?

Because the wheel cylinder is an essential part of the braking system, a lot can go wrong when it starts to go bad.

Read More:  When Should You Rotate Your Tires? (Tire Types + More)

If your brake pedal feels “mushy,” it is likely caused by the wheel cylinder. If they are not pressurizing correctly, these cylinders will not be able to extend the piston properly.

Therefore, the brakes will start to feel strange and a bit unresponsive.

Furthermore, their inability to pressurize will also slow your brake’s activation time. They’ll take longer to press against the brake shoe, in other words.

Of course, a car with a slower brake time is also more likely to end up in an accident. Usually, it will be much harder to stop a car with a bad wheel cylinder.

Sometimes, your car may even leak brake fluid because of damage to the wheel cylinders. Often, you’ll be able to detect this sort of damage visibly – usually by noticing a film of liquid on the backing plate.

However, sometimes, you may even notice pools or drips coming from the wheel cylinders themselves. Larger pools indicate that the vehicle will have a serious time stopping and should not be driven.

Can I Drive with a Bad Wheel Cylinder?

Can I Drive with a Bad Wheel Cylinder?

Usually, it is not safe to drive with a broken wheel cylinder in any situation. When this part of the braking system becomes damaged, it can seriously affect your car’s ability to brake.

Obviously, a car that has trouble stopping is not a safe car to have on the road. You never know when these problems are going to get worse or when you’re really going to need your car to stop quickly.

In many cases, even small amounts of damage to the wheel cylinder can cause serious braking problems.

Read More:  What Is A Wheel Offset? (All You Need To Know)

Furthermore, many wheel cylinders will leak out brake fluid when they are damaged. Even if it is a slow leak, any sort of leak could potentially cause your car to become seriously low in brake fluid.

If your car runs out of brake fluid, then it won’t stop at all. When the brake fluid is dangerously low, you may push the brake all the way to the floor without anything happening.

Unless you want to potentially drive a vehicle without any working brakes, you should not drive your car with bad wheel cylinders.

When Should Wheel Cylinders Be Replaced?

When Should Wheel Cylinders Be Replaced?

For the most part, each car has its own maintenance schedule. Therefore, when you should replace your car’s wheel cylinders varies depending on the car you have.

In many cases, you can find suggestions in the owner’s manual for when to change your wheel cylinders.

With that said, wheel cylinders commonly need to be replaced when the car is over 75,000 miles.

Because bad wheel cylinders can be so serious, it is essential to replace these pieces of equipment as soon as you need to.

Luckily, replacing a wheel cylinder is often not terribly expensive. You can expect to spend around $150 to $190 to replace one cylinder. Replacing more than one cylinder will likely cost more.

The exact cost will depend on your car and location.

What Causes Wheel Cylinders to Leak?

If they are never replaced, most wheel cylinders will leak eventually. With normal wear and tear, the piston seals on the wheel cylinder will eventually decay to the point of leaking.

Read More:  How Much Do Tractor Tires Weigh? (Types, Sizes + More)

There isn’t much you can do about this except replace your wheel cylinders as necessary.

Furthermore, moisture can sometimes build up inside the wheel cylinder, which can lead to corrosion and damage.

For this reason, if you live in an area with higher humidity, your wheel cylinders may break down sooner, usually due to corrosion.

Sadly, this leaving can be a serious problem. Once it gets into the brake linings, the fluid can cause uneven braking and other issues. Plus, if enough fluid is lost, you may be unable to brake at all.

Usually, the only way to fix one of these leaks is to completely replace the cylinder. Generally, there isn’t any way to repair old cylinders themselves.

To know more about wheels, you can also see our posts on what are wheel bearings, what are wheel weights, and wheel hubs.


Wheel cylinders are an essential part of the braking system. When the brake pedal is pushed, the wheel cylinders activate and put pressure on the brake shoes. In turn, these brake shoes put pressure on the drum and stop the vehicle.

If the wheel cylinders stop working, the car won’t be able to stop correctly (or at all). Therefore, they are extremely important for the car’s safety.

You have to replace these cylinders regularly, as they do wear out with use. In many cases, worn cylinders can cause leaks and other issues.

Leave a Comment