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Understanding your car's disc brakes and hardware

Understanding your car's disc brakes and hardware

If you're a little more 'hands on' than most and want to tackle some do-it-yourself jobs on your car or lorry, choosing the correct disc brakes and hardware is a great place to start.

What are disc brakes?

There are quite a few disc brakes out there. Some are more efficient than others, but they all are better than the best alternative - drum brakes. Disc brakes provide the best braking for an automobile. Let’s take a look at these:

Solid Discs

These are made from a solid piece of grey iron, and they reach their thermal  limit considerably sooner than other disc rotors, especially their heat characteristics.  However, they provided adequate performance for every-day driving.

Vented Discs

These serve to vent the rotor as they allow a greater amount of air to flow between the disk vents- thereby allowing the disk to run cooler. On the other hand, they are heavier than the plain disc.

Drilled Brakes

The next step in disc brakes allow for better heat dissipation. The holes drilled in the disk keep the rotor running cooler and last longer. Cross drilled holes are completely drilled through both disc surfaces allowing air to pass through and the heat to dissipate.

Slotted Brakes

The slots are positioned through both holes, and keep water and other debris away from the brake surface. The increase the surface area and let air flow through the brake, but they may weaken the rotor too.

Carbon Ceramic Brakes

The ultimate in brakes are composite brakes or carbon ceramic brakes, are made from a mixture of carbon and silicon heated to temperatures to 1,650 degrees Celsius, which is nearly as hard as a diamond. These are extremely strong, and are 50% lighter than iron discs. They are very, very expensive.  

Discover how to replace the brake pads on your car!

Understanding your car's disc rotors and brake hardware

What are drum brakes?

Many cars use disc brakes for the front wheels, because about 70-80% of the vehicle’s stopping power is done by the front wheels. Even so, the venerable drum brake is still used by some of today’s vehicles, but that is getting less and less every year.

The parking brake is also incorporated into the drum brake and the parking brake can thus be located in the rear drum brake. The manufacturer can thus offer plain-jane vehicles by offering drum brakes with a parking brake built-in at the rear wheels.

Vehicles with disc brakes in both the front and rear wheels do provide balanced braking  performance, especially in the wet.

Brake Hardware

Defective pad shims, clips, springs and other small parts can allow vibration and motion between the pads and the caliper, and this can create and magnify noise.

Replacement pads that don’t necessarily include new replacement hardware parts, should not be installed with just the old parts, even if it’s tempting to reuse them.

Check to see that new hardware is included with the new parts.

The new pads are held in place by the calipers but the clips or springs that fit between the pads and calipers are there to take up slack and to dampen unwanted vibrations.

Weak hardware will start to affect other brake parts causing unwanted part movement, binding, noise and other problems.

New hardware consists of springs, anti-rattle clips and other small brake parts that are necessary for brakes to function properly.

Even if a piece of brake hardware looks brand new, it should be replaced when the pads are replaced. Metal fatigue and heat can cause unseen damage that could cause the pads to wear prematurely.

It really is so important to include new brake hardware when doing a brake job. Disc brake hardware plays an important role in controlling noise and allowing the new brakes to stop quietly and efficiently.

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