Does your car need a brake caliper replacement? Often you can hear the sound of a pen dropping at the mention of brake calipers. This comes as no surprise. The brake calipers are a very important component of your vehicle’s braking system. However, its function isn’t widely known.
Yet, it should be.
When it comes to your vehicle’s braking system, emphasis is usually placed on the brake pads which need to be frequently replaced. However, on vehicles equipped with a disc braking system, the brake calipers are essential to its function.
The brake calipers help provide stopping power. When they fail, it compromises your vehicle’s overall safety. In this article, we’re going to explore how the brake calipers work and when they should be replaced.
What Is A Brake Caliper and What Do They Do?
The brake calipers are the heart of the disc braking system. This component enables the braking action to occur which enhances the safety and driveability of your car. There are different types of brake calipers. Knowing when there is a problem with the brake calipers can help you determine how to best troubleshoot them and ultimately have them replaced.
Put simply, the brake caliper is the component that pushes the brake pads into the rotor when the driver activates the brake. The caliper houses the brake pads and the pistons. The primary job of the brake calipers is to stop the wheels. The calipers squeeze the brake pads against the rotors reducing the vehicle’s speed.
The brake calipers make up the disc brake system. They have two main functions; they house and guide the brake pads. That’s why the brake pads are always within the right distance of the rotors.
How Do The Brake Calipers Work?
The brake calipers are critical in slowing down and stopping a vehicle. Here is a breakdown of how they work:
- When you press down on the brakes a piston puts pressure on the brake fluid in the master cylinder. This pressure flows to the brake lines, all the way through the hoses to the brake caliper pistons.
- The pressure from the fluid moves the caliper pistons out of the bore
- The brake pads are pushed forward to connect with the rotors
- The brake pads are squeezed against the rotors creating immense friction that opposes the motion of its spin.
- Depending on how hard you press on the brakes the calipers on each side of the caliper will either bring the vehicle to a stop or slow down the wheels.
- Once you stop pressing on the brake, the hydraulic fluid returns to the master cylinder and flows out of the brake caliper pistons
- This rapid drop in pressure causes the brake pads to release the rotors and the pistons are pulled back into the bore.
- The caliper then slows down or stops the spin of the rotors.
Where Are The Brake Calipers Located?
The brake calipers are located on the wheels. However, the location of the calipers sometimes depends on the design of the vehicle. In most vehicles, the brake caliper assembly is on the front axle and the calipers are configured to the vehicle’s steering knuckles by bolts or pins. Some vehicles are designed with brake calipers on both the front and rear wheels.
If you ever get the chance to inspect an actual brake caliper assembly you’ll find that it's shaped like a C-clamp. Most caliper assemblies are designed with:
- A dust boot that protects the calipers and keeps dust, debris, and other contaminants from making their way into the cylinder piston. This component is essential because the low position of the brake caliper and its open mounting design makes it easy for the cylinder to become contaminated.
- There are bleeder screws that allow you to remove air from the brake lines when replacing the brake fluid or when the brake calipers are being serviced.
- The piston rubber seal keeps brake fluid from leaking and helps the piston retract to its original position when the driver releases the brake pedal.
How Often Do The Brake Calipers Need To Be Replaced?
Unlike the brake pads, the brake calipers can last for several years. Calipers are manufactured from ultra-durable materials that are designed to be sturdy and resistant to all kinds of damage. The average lifespan of the brake caliper assemblies on a vehicle is approximately seven to ten years or seventy-five thousand miles.
It is important to note that how fast the brake calipers wear can depend on a variety of factors including driving habits, driving conditions, and the climate. Brake caliper assemblies are designed differently across brands. Therefore, the type, design, and overall quality of craftsmanship can contribute to its longevity.
When the brake calipers start to wear the seals harden and this increases the risk of sticking. Constant braking leads to intense heat being generated at the brake calipers, the pads, and the disc. Although the heat dissipates rapidly the regular heating and cooling action is what causes the brake calipers to wear.
Poor road conditions cause you to activate the brakes rapidly. This doesn’t just affect the rotors, the brake pads but it also accelerates the wear of the calipers. Regularly driving on such roads can lead to dirt and other corrosive elements building up in the brake calipers which also causes rapid wear.
Moisture also can be incredibly damaging to your brake calipers. Yes, moisture can be detrimental to all of the components within the brake caliper assembly which includes the pistons, the piston bores, and the caliper body.
Brake Caliper Replacement – Signs The Calipers Need To Be Changed
Corrosion, dirt buildup and a fluid leak can compromise the health of your brake calipers. It’s important to spot the signs of brake caliper failure early on before it becomes a major issue and leads to a big safety problem. Here are some of the top signs that your brake calipers need to be replaced:
Unusual Noises When Braking
Do you hear abnormal or weird noises whenever you push down on the brake pedal? High-pitched noises or sudden hard impact sounds whenever you activate the brakes can be a sign of sticking or loose calipers. In some cases, these noises can indicate brake pad wear but premature brake caliper failure can affect the brake pads.
Such unusual noises may also be accompanied by a peculiar burning smell which is a result of a stuck caliper constantly applying pressure to the brake pads. The braking system will begin to generate intense heat producing a burning smell.
Car Is Pulling To One Side
When the brake calipers fail you may notice that your car tends to pull to one side the left or the right whenever you hit the brakes. When the driver activates the brakes, the brake caliper squeezes the rotor. When the driver lets up off the brake pedal it releases the rotors. However, when the caliper gets stuck the calipers are unable to retract which causes the wheel to drag. Whichever wheel has the stuck caliper the vehicle will drag towards that side.
Brake Fluid Leak
Brake fluid leakage is another major sign of brake caliper failure. The calipers rely on the brake fluid pressure from the master cylinder to extend the pistons and slow down the wheels. When the calipers start to leak brake fluid the rubber seals and the boot on the caliper is completely worn.
If you notice signs of a fluid leak such as puddles near your front or rear tires you should have your vehicle serviced immediately. Driving a vehicle with a braking caliper that is leaking fluid is downright dangerous and it greatly reduces its stopping power.
Brakes Feel Like They Are Always Engaged
Does it feel as if the brakes are always engaged even when you aren’t stepping on the pedal? This is usually because the calipers are stuck or seized and the brake pads haven’t been fully released. You might even notice that your car has to work harder when you increase the speed.
Often a quick visual inspection of the brake caliper can tell you whether they need to be replaced or not. If you notice that the caliper assembly is heavily corroded then it's a good idea to have them further inspected.
Brake Caliper Replacement Or Rebuild
When the brake caliper seizes, it begins to put abnormal stress on the brake pads, or starts to leak fluid you will need to have them rebuilt or replaced. Replacing the brake caliper on your vehicle can be very expensive. Depending on the extent of the damage you may be able to have them rebuilt instead.
Brake Caliper Rebuild
Typically, brake calipers are rebuilt using a repair kit that includes all the important hardware that you will need such as the seals and O rings. A caliper rebuild is meant to restore the caliper’s efficiency by installing new parts on the old assembly. If you decide to have your brake calipers rebuilt you should have the job performed by a skilled technician. If the calipers are just stuck a mechanic may be able to repair them by having the calipers cleaned and fixing the cause of the problem.
The repair kits don’t include the pistons. If the pistons are slightly damaged the technician may be able to save them. However, if the caliper's pistons are scored or pitted you’ll end up needing to replace the brake calipers with new ones.
When the brake calipers are rebuilt they are sometimes taken apart. Dissembling the brake caliper assembly leaves room for error. This can create problems down the line. Therefore, a rebuild doesn’t always restore the brake calipers to near perfect condition.
A brake caliper rebuild is an affordable solution to prolonging the life of your vehicle’s disc braking system. Yet these repair kits are limited and can only repair minor caliper problems. If the caliper is in relatively good shape and only needs new seals or a piston boot a caliper repair kit can be successful at restoring the brake calipers to good working condition. In some instances, the damage is so severe that a replacement is necessary.
Brake Caliper Replacement
On the contrary, some technicians are against brake calipers being rebuilt and will encourage you to have them replaced instead. Using a caliper repair kit isn’t always enough on its own. More than likely your vehicle will require new brake pads and perhaps rotors.
A brake caliper replacement involves removing the old brake caliper assembly and mounting new calipers. A replacement is the best choice if the brake calipers have been on the vehicle for several years and the performance quality has dropped. Or if the calipers no longer have reliable braking power then replacing them is your safest bet.
If just one caliper is damaged in most cases you’ll be able to simply replace that one. Some mechanics may recommend that you replace them in repairs especially if it is the original manufacturer part.
Brake Caliper Replacement Vs Rebuild
When it comes down to it you’ll have to weigh the advantages and disadvantages of both options. If you are on a tight budget, a brake caliper rebuild can keep your brake discs going for a while. Oftentimes the caliper can fail due to minor issues such as loose sliding pins. In situations like this, replacing the brake caliper is an unnecessary expense. If there is no outward damage to the caliper a rebuild can be suitable especially if conducted by an expert.
Although a caliper rebuild is less expensive it’s a messy procedure and there is always a slight chance that the components weren’t reassembled in the right position. There’s also the possibility of repairing the caliper and it starts to malfunction soon thereafter. A brake caliper replacement will give you peace of mind. Not only does it guarantee a well-performing device but the new caliper assembly will last for several years. A brake caliper replacement can be a more cost-effective solution in the long run.