Brake pads are the area of a vehicle's braking system that are supposed to wear out as the brakes work to stop the vehicle. As such, they need to be replaced at regular intervals. Brake pads should be replaced when the brakes start to make high-pitched screeching sounds, or otherwise start to behave differently than normal. Many different kinds of materials are used to make brake pads, including ceramic and kevlar. Each of these has different properties that make it suitable for some vehicles, and yet unsuitable for others.
Brake pads also come in a few different grades, and should have the ECE R90 certification to ensure their quality. Lastly, the construction of OEM brakes and aftermarket brakes generally differs slightly, and this is something buyers should take into consideration when buying brake pads, whether in an automotive parts shop or online through eBay. By knowing the basics on brake pad types, certifications, grades, and construction processes, anyone can buy their next pair of brake pads with confidence.
Brake Pad Types
The materials used to make brake pads need to meet several important criteria. They should be able to handle high heat, and create friction between the brake and the brake rotor, in order to slow down the wheel. There are several materials used with these properties, including organic compounds, semi-metallic compounds, ceramic, and sintered metal.
NAO Brake Pads
Asbestos was used to make brake pads until the health risks of asbestos were discovered. These have now been replaced by Non-Asbestos Organic compounds (NAO pads) that are made from organic materials like carbon, glass, kevlar, and rubber. These tend to be soft compounds which wear out faster than semi-metallic pads, and they also tend to create quite a bit of dust. However, a softer formulation means less noise and longer rotor life. Organic pads have to have less than 20 per cent metal by definition.
Semi-Metallic Brake Pads
Semi-metallic pads have anywhere from 30 to 65 per cent metal. The metals used include steel wool, copper, steel, and other metals that can absorb heat well. Since they are harder than other materials, they last much longer. However, they generally wear out the rotor sooner than other types, for the same reason. They are also noisier than most other types. Despite these drawbacks, semi-metallic brake pads are the most common type because of their excellent performance at high temperatures. They are especially useful in racing and sport applications for this exact reason.
Ceramic Brake Pads
Ceramic pads use ceramic fibres along with other materials in the pad matrix. Ceramic is a relatively clean material used for brake pads because it only generates a small amount of dust. They are also quiet and work well at both high and low temperatures. However, ceramic pads are often more expensive than other types. Ceramic brake pads are a good choice for regular street use. Be aware that there is currently no standard for how much ceramic the brake pads have to contain. This means many cheaper or unknown brands often sell 'ceramic brake pads' that actually have very little ceramic, and so provide sub-par performance.
Full-Metallic Sintered Brakes
Sintering is a process performed to fuse metal particles to other elements. This special process is used to make brake pads with a very high metal content. Full-metallic pads can be found in copper and bronze. Most formulations avoid iron, as this can potentially discolour the wheels. As with semi-metallic pads, full-metallic pads can be expected to have a long life, be noisy, and offer excellent performance in demanding conditions.
ECE R90 Brake Pad Certification
In the 1990s, the market for brake pads was flooded with cheap low-quality imported brake pads, creating a serious safety issue for consumers. This was addressed by legislation in the UK called ECE R90. Regulation 90 stipulates that all aftermarket brakes must pass rigorous testing in order to ensure that they are of the same, or better quality, than the OEM brakes that the vehicle came with. This regulation successfully shut down the influx of low-quality brakes. Today, all brake pads must be ECE R90-certified. This certification is clearly printed on the pads. It is especially helpful to ask for, and look for this certification when shopping online.
Brake Pad Grading
Many people do not know that brake pads are graded by friction level. The FMSI friction level code is used in many countries, and assigns a letter grade to each brake pad depending on its quality. The grades range from E, which is the lowest grade, to H, the highest. Most cars in the UK use grade G brakes, which are excellent. Grade H is usually reserved for motorcycles. Needless to say, those with grade G pads should not settle for a lower grade. On the other hand, those driving with level E or F pads should feel a significant improvement in braking power by upgrading to level G.
Some brake pads have two letters together, for example 'GG'. This indicates the cold braking power and the warm braking power, in that order. Metallic brakes, for example, might have a lower cold braking grade and a high warm braking grade, since the friction level in the material in the pads is more susceptible to temperature. Look for the FMSI code on the back of brake pads.
Other manufacturers label brake pads as 'heavy duty' or 'medium duty'. There is no recognised standard for these labels so understanding these labels is a question of reading the manufacturer's description carefully.
Brake Pad Construction
The fact that brakes from the original vehicle manufacturer are far more expensive than aftermarket brakes is not news to anyone. However, there is an important reason for the price difference. OEM brake pads are made with a different process than aftermarket brake pads. Aftermarket brake pads are most commonly 'flash-moulded' and glued, while OEM brakes go through a process called positive moulding.
Positive moulding is a process in which the brake pad friction material and the shim are heated together and pressed until they fuse together. This creates a uniform density throughout the friction material. Positive moulding is more expensive, however positive moulded brakes do not have to be 'bedded' or broken in before they can be used. They are also sometimes called 'low resin' brakes. There are very few manufacturers that make positive moulded aftermarket brakes, but they do in fact exist.
Flash moulding requires a much higher resin content in the friction material in order to press it into shape. The friction material alone is moulded, and then the shim is attached to the back with glue. Formulations with a high resin content may experience fade. This means the brakes react as they should upon applying the brakes, but the braking power rapidly decreases as the brake is held down. In contrast, positive moulded brakes have a constant braking power for the entire duration of the time the brakes are applied. Stopping distances are generally much longer for flash moulded brakes than for positive moulded brakes.
How to Buy Brakes Pads on eBay
Brake pads are easily found online at competitive prices on reputable sites like eBay. eBay makes it simple to find both the correct brake pads and a reputable seller, with eBay's unique public feedback system and advanced search options.
Finding brake pads on eBay is as simple as entering the search term 'brake pads' in the search box on any eBay page. The search can be refined by various criteria like category, condition, and price. Once you are searching within the correct subcategory, you can also search by make and model of car. This is a fast way to find compatible brake pads for any car.
As with any online transaction, choosing a reputable seller is important for your peace of mind. This is easy on eBay because every seller has a feedback score based on the level of positive feedback they have received from buyers during their entire history on eBay. By choosing a seller with a high feedback score, or better yet, one of eBay's Top-Rated Sellers, who have award icons next to their names, you can ensure that you are doing business with someone who has a history of excellent customer service.
The main consideration when replacing brake pads is the friction material they are comprised of. Friction materials can have high or low metal content, organic materials like carbon, rubber, and glass, or ceramic fibres. There are dozens of formulations that attempt to achieve a good balance between durability, like the harder compounds, and braking power, like the softer formulations.
One also needs to check the brake pad R90 certification to ensure that the pads have passed safety testing, and the friction level grade, which gives an idea of the stopping power the brake pads provide. Last but not least, buyers should compare prices on aftermarket and OEM brakes and consider whether the high-quality manufacturing process of OEM brake pads is worth the extra cost. By considering these factors and learning how to shop for brake pads online, on trusted sites like eBay, buyers can find the right brake pads easily and order them from the comfort of their homes.