How do brake pads work?
In the early days of the automotive industry, brakes consisted of nothing more than some wooden blocks and a lever. However, as faster, more powerful vehicles were invented, more reliable braking solutions had to be developed.
The modern hydraulic braking systems that we rely on today typically consist of brake pads, calipers, metal discs, and a range of cylinders and pistons. The pads are among the most critical car components as the friction they generate by applying pressure to the brake discs is what enables the system to slow the wheels down.
As soon as the driver presses down on the brake pedal, hydraulic fluid is forced through the system to the calipers, pressing the brake pads against the discs. There are normally four brake pads per axle – one pair for each wheel.
The components essentially consist of a metal backing plate which is lined with a special friction material. They are designed to withstand the extreme heat and pressure that is generated during braking. However, over time, the material wears down, becoming less effective.
Types of brake pads
The materials used to manufacture the parts will often determine their braking performance and durability. Each product will have different properties which are better suited to certain types of vehicles or driving styles. The main types of brake pad are organic, ceramic, low-metallic, and semi-metallic pads.
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Organic
Nowadays organic components are made from materials such as heat-resistant glass, rubber, and natural resins. Kevlar is often used in these products as it doesn’t generate as much pollution and is easy to dispose of.
One of the main advantages of these components is that they’re much cheaper and quieter than metallic parts. However, they also wear faster because the friction material is softer, generating a lot of dust. They are unsuitable for heavy duty or high performance vehicles, but ideal for small, lightweight cars.
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Low-metallic
These components are made with up to 30% metal, making them slightly more durable than fully organic components. However, they tend to be noisier and still produce a lot of dust.
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Semi-metallic
Most vehicles use some form of metallic pad for braking. They are made using a combination of synthetic materials and metals like copper and steel to produce a hybrid metallic compound.
This enhances their braking performance and makes them more resistant to heat than the softer pads. On the other hand, due to their higher metal content, they are also heavier and can wear the discs down. Moreover, they also have a fairly low friction coefficient, meaning that it may take longer and require more power to brake in cold temperatures. They are ideal for heavier vehicles.
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Ceramic
These lightweight parts offer high durability and excellent braking and heat resistance properties, making them a great option for high-performance vehicles. The frictional material is made up of ceramic fibres, fillers, and bonding agents which sometimes contain copper. They last a long time and produce less dust than other types. The downside is that they are quite expensive.
In addition to the materials and sizes of the products, you should also consider the brand when choosing brake pads. It is recommended to purchase products from reliable manufacturers that meet industry standards. Examples of trusted brake pad brands include RIDEX, BOSCH, Textar and TRW. You will also need to make sure that the parts are compatible with your vehicle.
The standard RIDEX 402B0011 brake pad set is compatible with most popular models from carmakers such as Audi, VW, Honda, Vauxhall, and many more. They have an optimal friction coefficient, reducing the overall braking distance, and the set consists of two pairs.
How often should they be replaced?
This varies significantly depending on the quality of the product and the way the vehicle is driven. The service life can range from anywhere between 30,000 and 70,000 miles.
Some brake pads come with built-in wear indicators which cause a loud squealing sound when the components need to be replaced. If you can hear screeching or grinding sounds and the brake pedal is vibrating or the car pulls to one side when you brake, it is probably time to install new pads. If one pair of brake pads needs to be replaced, you should replace the other pair on the same axle at the same time to avoid uneven wear.
