What Causes A Sticking Brake Caliper And How To Fix It?
Stick brakes are something that probably every car owner will experience at least once in their lifetime. Car brakes may seem like a simple thing, but they are actually a very complicated system that requires a lot of maintenance. In this article, we will explain what causes brake calipers to stick and how to prevent them. So let’s start with what causes brake calipers to stick.
What causes brake calipers to stick?
The most common reason for a brake caliper to stick is rusted caliper pistons due to damaged piston bellows. It can also be caused by brake pads sticking and squeezing the brake disc. In the case of rear brake calipers, the handbrake cable may be faulty.
However, there are several other rare reasons why a brake caliper may stick, so we will look at those as well. Here is a detailed list of the 7 most common reasons for a stuck brake caliper:
1. Rusty Brake Caliper Pistons and Piston Sleeves
Brake caliper pistons are a vital part of the braking system. They force the brake pads against the brake disc to slow your car down. The pistons in your brake calipers are encased in rubber sleeves to prevent dust and other particles from getting into the braking system.
Often this cuff becomes damaged, allowing water and other dust to get inside the piston. As a result, the pistons start to rust and eventually stop moving completely, causing the brake pads to stick to the brake disc. Check the caliper bellows for damage and lift it a bit to see if it’s rusty. If it is, you can push the piston out and clean it a bit. But don’t forget to replace the bellows, which can be difficult if you don’t have the necessary knowledge. Replacing the entire caliper is often not that expensive, so it’s actually recommended over rebuilding.
2. Rusty and Stuck Brake Pads
The second most common cause of a stuck brake caliper is actually rusted brake pads. Brake pads have guides that need to be lubricated to allow the brake pads to slide back and forth smoothly on the caliper mounts.
If dust or rust accumulates on these bracket guides, the brake pads will get stuck on the brake pad brackets and squeeze the brake disc. To fix this, you will need to remove the brake pads, clean the brake pad mounts with a file or sandpaper, and lubricate them with copper paste or something similar.
3. Dirt on the brake caliper guide pins
The caliper guide pins are located on the caliper brackets and help the caliper slide back and forth when braking. Usually these guide pins get hard due to rust and this will prevent the brake caliper from working properly and cause the brakes to stick.
These guide pins are covered with rubber sleeves to protect them from water and dust. Inspect the rubber boots, remove the guide pins to clean them and lubricate them again. A burner to heat the pins when removing them is a must, as they are tough to remove if they have been stuck for a while.
4. Parking brake steel cable
If the caliper sticking problem is coming from the rear of the vehicle, it’s most likely a problem with the parking brake. In many modern cars, the handbrake is located on the brake caliper, not inside the brake disc. Water and other dust can get into the handbrake cable and cause it to rust.
This will prevent the brake caliper from releasing properly when you release the handbrake. To fix this, lubricate the handbrake cable and caliper arm and try moving it back and forth 100 times to see if it makes any difference. In the worst case scenario, you may need to replace the parking brake cable or brake caliper.
5. Broken Brake Hose
Brake hoses allow brake fluid to flow through the brake system and back to the master cylinder. However, if there is a small crack in the brake hose, the brake fluid can flow back to the brake piston.
This can cause the brake caliper to stick. This is not a very common problem, but I have noticed it happening on some cars. If you have tried all other methods and the problem persists, try replacing your brake hoses.
6. Dirty or old brake fluid
In fact, dirty or old brake fluid is the main cause of many brake problems. Brake fluid absorbs moisture from the air, so it should be changed every 1-2 years. If you don’t change it, a lot of water will get in and your brakes will rust from the inside.
How to prevent brake calipers from sticking
If you maintain your brakes regularly, most of these problems won’t occur very often. There are a few things you can do to avoid such problems in the future. The most common ones are:
>> Change your brake fluid every 1-3 years to prevent the inside of your brake system from rusting.
>> Clean your brake pads, guide pins and pistons every 2-3 years. Clean them thoroughly at least when you change your brake pads or brake discs.
>>> Sometimes you have to brake suddenly when driving at high speed. Some people may think that it is better not to use the brakes of the car, but in fact it is the opposite. If you do not brake hard, the car will stop moving after a while.
>>> A lot of people drive short distances and never use their brakes properly. You need to use your brake hard at high speed some times per year to prevent them from getting completely stuck.
>>> Use your parking brake even if you have an automatic transmission. Another common problem is that you never use your parking brake if you have an automatic transmission. This will cause the parking brake cables or bracket to get stuck the single time when you use it.
