Learn Everything About Rear Brake Hardware

Rear brake hardware is basically the hardware parts used in rear brakes to support the brake assembly and help in functioning of brake components smoothly in a vehicle.

Rear Disc brake mainly comprises the following parts:

• Brake disc or brake rotor
• Brake pads
• Wear indicator
• Brake caliper assembly
• Wheel hub

There are various materials used for manufacturing different hardware parts. But there are some common materials used for making rear brake hardware kits, so let’s gain some knowledge about them.

Brake shims or anti-squeal shim are thin layers made of rubber or metal like titanium. Banjo fitting bolt is usually made up of steel material plating with zinc and copper washer is used for fitting. Pistons are made of aluminium or chrome-plated steel. Caliper pins are metal pins and the pin boot is typically made of rubber.

Here are the features you must look into while purchasing your car rear brake hardware:

• Make sure that renewal of pads is easy and quick.
• There should be availability of a wide choice of friction material.
• It should be designed with proper functionality and a reliable braking system.

Majority of rear brake hardware parts are found attached in brake caliper assembly for proper functioning of brakes.

• Bleeder screw is at the top of the brake caliper provided with threads to fit in it and can be removed easily.
• Brake pad shims are thin layers of metal or rubber found between the brake pads and rotor attached to the pads.
• Banjo fitting comprises a hollow bolt inserted into a caliper frame through a banjo connector and soft metal washers on each side.
• Lock bolt is inserted into the guide pin through a hole in the caliper.
• Guide pin is fitted in the caliper's part assembly between the caliper bracket and caliper frame.
• Pin boot is like a rubber bellow which covers the guide pin or caliper pin in caliper assembly.
• Bushings are fitted to the end of the guide pin. It is inserted into the guide pin hole provided in the caliper bracket.
• Spreader spring is adjusted in holes provided in each brake pad.
• Pad clip or retainer is fitted in the space provided in the caliper bracket in caliper assembly.
• Piston is in the caliper frame in the caliper bore.
• Piston ring is fitted around the piston inside the caliper frame.
• Square cut piston seal is found attached around the piston where it fits tightly.

Have a look at the working of the rear brake hardware below:

1. Bleeder Screw - Bleeder screw or valve is used for brake bleeding in a hydraulic brake system. Basically, bleeding is done when the air bubbles get trapped in the hydraulic brake system.
2. Brake Pad Shims - It works to fix the imperfections between the pads and rotor and to reduce noise induced between them. Pad Shims even dampen the vibrations.
3. Banjo Fitting - Brake fluid flows from brake / flex hose into piston through the banjo hollow bolt and its fittings.
4. Lock Bolt - It is used for locking between brake caliper frame and guide pin.
5. Guide Pin - To guide the caliper frame and bracket and align them. It is also known as a sliding pin / caliper pin which allows the caliper to float or to slide when brakes are applied.
6. Pin Boot - This boot can contract and expand when the brake works. It is used to prevent the entry of dust inside the caliper pin or guide pin hole.
7. Bushings - It is used for fitting and covering the caliper pin or guide pin.
8. Spreader springs - It is used to unload the brake pads from the rotor after operation of brakes.
9. Pad Clips / Retainer - Its work is to support the brake pads and pads retract back smoothly because of retainer after braking.
10. Piston - It is used to push the brake pads against the rotor to retard the motion and stop the vehicle.
11. Boot Ring / Dust boot - It prevents dust particles to flow in the piston. Piston ring also known as a boot ring or dust boot, is used to fit the piston inside the caliper bore.
12. Square Cut Piston Seal - Square cut piston seal is used to prevent the flow of fluid outside the piston into brake pads while operating brakes.

There are some common problems which we can find in rear brake hardware:

• Damage such as stripping of threads in the caliper pin.
• Excessive corrosion in hardware parts.
• Cracking or tear of pin boots.
• Dust gets trapped on wheels, calipers and other components.
• Damaged or corroded brake pad clips.
• Scoring, wear on Piston and not working properly.

This all leads to problems in rear wheels braking force system, such as:

• Pedal pulsations
• Brake noise
• Vibrations
• Leaking
• Brake fail to release

The symptoms and causes of problems in the rear brake hardware are:

1. Pedal Pulsations - Pulsations felt in the brake pedal is often because of a disc with an excessive run out or uneven thickness. Rotation of the disc pushes the piston back to their bores. This movement is carried back to the brake pedal through the master cylinder. A loose wheel bearing and tight caliper slides also cause pedal pulsation.
2. Brake Noise - Noise is a common problem to complain about disc brake and no need to worry much about it if proper precautions are taken. Sometimes we hear a rattle sound at slow speed this is because of loose brake shoe / pads in the caliper. Squealing is more often in the brake, this is because of brake shims. This shim dampens the vibrations between pad and caliper that are heard as brake squeal. Usually it occurs if shims are missing or worn out. However, a scraping disc noise occurs when lining wear sensor is scraping the disc or if there are loosened caliper bolts.
3. Vibrations - This is more often because of worn out brake shims or other hardware parts. Even if the shims are missing or pads are worn out, then vibrations take place. Vibration could be also because of Disc Thickness Variation (DTV).
4. Leaking - A caliper may leak brake fluid because of a damaged or worn out piston seal. Leaking is also caused by a rough surface on the piston or in the caliper bore.
5. Brake cannot Release - Brake cannot release because of caliper piston not retracting or getting stuck. It also fails, because of sticking pedal linkage, master cylinder not releasing pressure. Even because of restricted pipes, hoses, or banjo bolts.

Isn't it interesting to change the rear brake hardware and extract knowledge about its components? If we wish to do so, we must need some basic tools so you can replace brake hardware. Tools we need are:

In the market you will find various brands for rear brake hardware. But which brand should we choose, which is better? Are we confused to go for a particular brand? As quality of hardware plays a vital role for functioning of the rear braking force system, we should use optimized and reliable hardware for rear wheel braking systems. So, for that we have listed some top brands which manufacture high-quality hardware parts for rear disc brakes available in parts avatar.

• Worldparts Brake Cables Rear Brake Hardware
• Dorman/First Stop Rear Brake Hardware
• Dorman/Autograde Rear Brake Hardware
• Raybestos Rear Brake Hardware
• Auto Extra Rear Brake Hardware
• Dorman/Help Rear Brake Hardware
• Absco Rear Brake Hardware
• Dorman (OE Solutions) Rear Brake Hardware

Now we all are aware about how the rear brake hardware is used. Let's also see some parts related to it.

• Brake disc or brake rotor
• Brake caliper
• Rear brake cable

Rear brake hardware typically gets worn out or need to be replaced after certain kilometers or even in every brake job depending on the condition of it. It’s not so difficult to inspect and replace some brake hardware parts. Keep on reading further to learn how to replace brake hardware:

Step 1 - Remove 1/3rd to 2/3rd of brake fluid from the master cylinder reservoir to prevent it from overflowing when the pistons are pushed in.

Step 2 - Set the ramp or car jack to car body and lift it above the surface up to a certain height

Step 3 - Remove the wheel by removing all the nuts fitted to it and also take care of the wheel cylinder while doing this.

Step 4 - Use a C clamp and tighten it to force the piston back into the caliper bore.

Step 5 - Remove the mounting hardware like a caliper pin and lift off the caliper by supporting it with a wire hook so that the caliper does not hang from the brake hose.

Step 6 - Inspect the caliper pin if it needs to be replaced and then remove the pin boots and inspect if any sign of tear or crack in it.

Step 7 - Remove the old pads or shoe from the caliper bracket and inspect for any uneven or wear appearance which shows hardware issue. Also, remove the pad clips and replace it along with extra pads. This will reduce noise and vibrations.

Step 8 - Clean the caliper frame with cloth and remove dust boot, piston and its seal and inspect whether to be replaced.

Step 9 - As, we have removed the components, inspected all and replaced them with new hardware if required and reversed the steps for caliper assembly. Make sure the piston is pushed back to the cylinder.

Step 10 - Position the caliper over the disc and install all mounting bolts.

Finally, we have replaced the rear brake hardware successfully.