What Is a Brake Caliper?

The process of how your brakes work doesn’t start and end when you step on the brake pedal. 

The braking system needs to pull a lot of strings for your vehicle to slow down and come to a stop. One of the many parts that play a huge role in generating enough stopping power is the caliper on your car’s brakes.

The Basics of Car Brake Calipers

The car brake caliper is a part of the disc brake assembly. Excluding the rotor, the caliper is considered the largest part of the assembly, housing the brake pads and a piston or pistons.

Where are the Brake Calipers Located?

Caliper brakes can be installed in the front and/or rear wheels. If the disc brakes are in front, the caliper typically mounts to the spindle, caliper support bracket, or steering knuckle.

Meanwhile, rear disc brake calipers are mounted to a support bracket on the axle flange or suspension.

How Do Brake Calipers Work?

As the driver steps on the brake pedal, the brake fluid becomes pressurized, creating a mechanical force that pushes the caliper pistons against the brake pads.

As a result, the brake pads come into contact with the rotor.

Brake noise is common in a disc brake assembly, and as long as the brake linings aren’t worn out, the squeaking and squealing noises are pretty normal.

But because most people don’t like squealing brakes even if it’s considered “normal,” most pads have a rubber-coated steel shim on the pad backing plate to prevent the resonant vibration between the pad and the rotor from being transmitted to the caliper and its bracket. 

The noises from this brake setup are often due to the high-frequency rattling or vibration of the brake pads, which are housed in the calipers.

Manufacturers are well aware of this issue, which is why most brake calipers come with anti-rattle clips or springs to keep the pads in place under tension, reducing vibrations in the process.

Pro Tips are nuggets of information direct from ASE-certified automobile technicians working with CarParts.com, which may include unique, personal insights based on their years of experience working in the automotive industry. These can help you make more informed decisions about your car.

Pro Tip: The metal clips that go in the caliper bracket are made to mitigate rattling or clicking noises the pads might make moving around in the caliper cage.

Some caliper designs also have special metal or fiber shims between the brake pad and caliper pistons to help dampen vibrations.

Types of Brake Calipers

There are generally three types of brake caliper designs: fixed, sliding, and floating.

Fixed Caliper Design

The fixed caliper design is the earliest type of brake caliper ever created. It has the caliper body manufactured in two halves with two to six pistons applying the brake pads upon stepping on the brake pedal. 

Fixed calipers will have an inner set of pistons and an outer set of for the very reason that the caliper is “fixed” and doesn’t float. Fluid has to be fed to both the inner and outer pistons.

A fixed design means the caliper is mounted rigidly to the suspension, and no part of the caliper except the pistons will move when the brakes are applied. 

Fixed calipers are somewhat heavier (although both kinds of calipers may be made of aluminum), which means they’re better at dissipating and absorbing heat compared to the other designs. This feature lets the brake rotor and pads run cooler, which means less heat is carried to the brake fluid. 

A fixed caliper design is suitable for vehicles that frequently require repeated hard stops because the caliper is less likely to contribute to heat-induced fade or vapor lock in the hydraulic system.

Pro Tips are nuggets of information direct from ASE-certified automobile technicians working with CarParts.com, which may include unique, personal insights based on their years of experience working in the automotive industry. These can help you make more informed decisions about your car.

Pro Tip: High-performance European and Asian sports cars usually have fixed calipers.

Unlike other designs, a fixed caliper isn’t flexible, resulting in a firm and linear brake pedal feel.

However, the downside to using a fixed brake caliper is that it adds weight to the vehicle. The number of pistons and split bodies also increases the risk of developing leaks.

Floating Caliper Design

In a floating caliper (or pin-slider) design, bushings or o-rings support the body, making it “float.” This type of design doesn’t let the body come into contact with the anchor plate, hence the name.

The pins, sleeves, bushings, and o-rings of a floating caliper should always be lubricated to prevent the caliper from binding or sticking. If left unaddressed, the problem can result in a loss of braking power and premature brake pad wear.

Sliding Caliper Design

In a sliding caliper design, the body has direct metal-to-metal contact with the anchor plate.

Unlike a floating caliper, this design doesn’t use pins and bushings. Instead, it moves on ways that were cast and machined into the caliper body and anchor plate.

Both floating and sliding calipers have moving bodies every time the brakes are applied. Both calipers move within a limited range on the anchor plate that’s mounted to the suspension.

As the driver steps on the brake pedal, the caliper piston moves out of its bore. It applies the inner brake pad while the body moves in the opposite direction, applying the outer brake pad in the process.

Compared to a fixed caliper, both floating and sliding calipers are cheaper to produce and feature a simpler design.

Pro Tips are nuggets of information direct from ASE-certified automobile technicians working with CarParts.com, which may include unique, personal insights based on their years of experience working in the automotive industry. These can help you make more informed decisions about your car.

Pro Tip: However, the pads are easier to replace on fixed calipers. You just have to retract the pistons with a screwdriver and remove a couple of pins to lift the pads out and slide new ones in. Removing the caliper is not necessary to just replace the pads on a fixed caliper.

Both floating and sliding calipers have fewer pieces than a fixed design, making them easier to service and less susceptible to leaks.

Both types, however, have flexible bodies that can contribute to a spongy brake pedal feel. The body also tends to twist slightly when the brakes are applied, resulting in tapered wear of the brake pad lining material.

Lastly, because these designs are lightweight, they’re not as efficient as dissipating heat like fixed calipers. Their flexible mounting systems tend to slow down heat transfer from the caliper body to the anchor plate.

Brake Caliper Maintenance

Brake calipers are designed to last longer than brake pads, but that doesn’t mean they’ll last forever. Driving with worn-out brake pads will generate too much heat, which can warp the rotors and calipers.

Some experts may recommend servicing your disc brakes once every 12,000 miles or at least once a year, but usually you’ll get 50,000 miles or more out of a set of brake pads. Some brake pads may last 100,000 miles.

Usually, you’ll get 50,000 miles or more out of a set of brake pads. Some brake pads may last 100,000 miles.

–Richard McCuistian, ASE Certified Master Automobile Technician

Washing your car regularly can also help remove debris and other contaminants that can easily corrode the calipers and other exposed brake parts.

Key Takeaways

The brake caliper houses the brake pads and pistons. Stepping on the brake pedal will generate hydraulic pressure, pushing the pistons onto the brake pads that will come into contact with the brake rotor.

Calipers generally have three designs, including fixed, floating, and sliding. A fixed caliper means the body is mounted to the suspension, while sliding and floating calipers have flexible bodies that have a specific range of motion.

Brake calipers are subject to corrosion and other issues, which is why experts recommend servicing them once a year or every 12,000 miles to ensure proper brake system operation.

Get High-Performance and OE Brake Calipers Online

As discussed earlier, brake calipers press the brake pads onto the brake rotors to slow down your vehicle. Bad brake calipers may cause issues such as uneven braking, squealing noises, and reduced braking power. While these might not seem significant, they can put you and your passengers at risk of accidents. Your braking system needs to always be in tip-top shape for your safety. Good thing CarParts.com is a trusted source for all kinds of brake components.

Here at CarParts.com, we have a wide selection of brake components that are made following the precise specifications of the original parts. This ensures that the replacement will function just like the original. Aside from providing high-quality parts from reputable brands, we’re committed to offering them at a more affordable price.

Need new brake calipers? Check out our selection here at CarParts.com and shop for a set today!