brake caliper sticking

Brake Caliper Sticking – Causes and how to fix it

In Brakes by Magnus Sellén1 Comment

brake caliper stickingDriving a car without functionally brakes is really stupid.

Brakes help bring your car to a halt when you are speeding. Brake calipers are attached to rotors on all the car wheels. When you apply brakes the calipers will hold tightly to the wheel hence helping your car to come to a complete halt.

Brake pads wear out and need to be replaced when they stop gripping the wheel tightly.

Reasons why your calipers are sticking

Brake calipers do stick but not all the time. There are several things that could cause the calipers to stick, here are some of the most common reasons.

1. Worn/Damaged Caliper pistons

Just like the caliper bolts, the pistons have a rubber boot on the outside. This plays a vital role of protecting the pistons. But, during periods of mechanical service the rubber can be torn by mistake letting in dirt particles. This debris can cause the calipers to stick.

2. Worn out brake pads

Brake pads come into contact with the rotors hence helping stop the vehicle. With time the pads wear out and this causes the brake calipers to become sticky.

3. Dirty caliper slides

Caliper slides are grooves within the brake caliper that hold the brake pads when you press the brake pedal and let the pads loose when you let go of the pedal. However, with time the shims have an accumulation of debris and this causes them not to hold the brake pads tightly. This will cause the brake calipers to stick. You can fix this by simply cleaning the shims.

4. Handbrake/E-brake cables

Sometimes the E-brake is fitted inside the rear calipers of your car, and if the hand brake wire is worn out, it may cause the caliper to stick.

5. Caliper bolts

The caliper bolts will secure the calipers in place. On the outside, the bolts have rubber boots that ensure that they are well lubricated. If there is tear on the bolts then you will have problems sliding them in.

Besides, the wear and tear lead to accumulation of debris which will cause the calipers to stick. You can replace your bolts and this should solve the problem. In extreme cases, you may be forced to replace the entire brake calipers. Over tightening the bolts can also cause them to break while driving.

6. Broken brake hose

The brake hose allows brake fluid to flow to the braking system and back to the master cylinder. However, if there is a small breakage in the brake hose the brake fluid will flow to the brake pistons but not back. This will cause the calipers to stick. You can rectify this by lifting the car off its wheels and stepping on the brakes. Next, try rotating the wheels. If this does not work then you will have to replace your braking hose.

How the braking system works

car brakesThe primary function of the braking system is to bring the car to a complete halt at high speeds. You do this by pressing on the brake pedal. A hydraulic system will be activated and brake fluid will flow to the calipers hence helping the brake pads clap on the rotors.

In some cars, brake boosters will be used to help the car stop faster. The boosters ensure that the driver uses minimal effort when applying the brakes. Modern cars all have Anti-Braking System (ABS).

The ABS is an electronic system that uses wheel sensors to know the amount of pressure to be supplied to the wheels. ABS works with the onboard computer and traction control systems to help the driver maneuver the car during slips and unfavorable driving conditions.

The handbrake prevents the car from rolling when the car is at a complete halt. In extreme circumstances, the driver can use the handbrake to stop the car when the brakes fail.

The front brakes often play a bigger role in bringing the car to a halt than the rear ones. This does not mean you should replace one and ignore the other. Whenever you engage the brakes force is shifted forward and this puts more pressure on the front brakes. This is the reason you will find drum brakes on the rear and disc brakes on the front.

Cars with all wheels having disc brakes tend to be high-performance cars. When you are speeding the front wheel brakes may lock and this forces the car to skid. This has led to manufacturers designing more complex electronic braking systems that do lock.

Signs that your brakes need some maintenance

Brake pedal remaining down: Whenever you press the brake pedal down it should automatically come up after you let go. This is because the braking system uses hydraulic fluid to operate. If your braking system is not working well then the braking pedal will remain down even after use.

Car shifting fast after braking: When you have sticky brake calipers the car will shift to the left or right whenever you press the brake pedal. This is a sign you have problems with the caliper bolts, pistons, hose or slides. These should be checked immediately and replaced.

Brake fluid leakages: You cannot drive a car that has leaking braking fluid. The fluid is vital for maintaining the cars braking hydraulic system. If you notice some fluid under the car’s wheels then you could be leaking brake fluid. Take your car to a mechanic immediately before you are involved in a road accident.

Difficulty getting the car to a halt: This is the most obvious symptom of faulty brakes. If you have difficulty stopping the car even after pressing the brake pedal, it could be that your brake pads are worn out. The brake fluid could also be leaking.

Grinding metal noise: If you notice that your car is producing high pitched sounds whenever you apply brakes it could be that the pads are worn out and the thin sheet underneath them is coming into contact with the rotors. It also is caused by sticking brake calipers. The sound is both irritating and embarrassing.

Conclusion

Anytime you have issues with the brake calipers you will have problems stopping the car. This can be dangerous especially when you are traveling under high speeds. The brake calipers have pads attached to them that clap on the wheel rotors. If your bolts and pistons are not well lubricated due to a mechanical fault then the brake calipers will stick.

Hello I'm Magnus, the owner and the writer of this website. I have been working with cars since I was 16 and I'm specialized with in-depth Automotive diagnostics. Also been driving drifting for the last 6 years. I'm here to give you answers to all your automotive questions and I hope that you enjoy our content.

Comments
  1. Just had back brakes put on. My car sits a lot. Why do I need calipers on one rear wheel? The mechanic could see this ? Why suddenly? The cause so soon after new brakes?

  2. Due to a very high demand and high ammount of comments, you have to wait for some time for your car questions to get answered. If you want to get fast answers from a certified master technician you can ask your questions here:
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