Brake Pads: Choose & Use Safely

There are three common types of brake pads on the market: resin-based, metal-based, and ceramic-based. While the names may seem a bit different, their practical performance varies significantly. Choosing the right type depends on your car and your driving style. There are also many subtle details to consider during daily use, otherwise safety issues can easily arise.

Brake pads actually work very simply: they use friction to dissipate the car's momentum into heat. Therefore, when choosing a material, ensure it offers sufficient friction (for effective braking), resists wear (to ensure long-lasting performance), withstands high temperatures (otherwise, the brakes become ineffective at high temperatures), and is quiet (otherwise, constant noise can be annoying).

Let's start with resin-based, also known as organic brake pads. These primarily use phenolic resin to bond cellulose and graphite together. Some pads also contain a small amount of metal powder for added strength. These pads are currently used in over 70% of family cars.

These brake pads offer stable friction at room temperature, won't wear the brake disc too much, and are quiet when you apply the brakes. They also stop quickly even in winter, and they're reasonably priced. However, they're somewhat heat-sensitive, and can easily break down at temperatures above 350°C.

For example, they can become less effective after continuous downhill driving on mountain roads or sudden braking on the highway. While they should be replaced after 30,000 to 50,000 kilometers for a typical family car, they're suitable for sedans and MPVs used for daily city commuting.

Metal-based pads are categorized as semi-metallic and full-metal. Semi-metallic pads contain 30% to 50% metal particles, such as steel and copper fibers, mixed with resins and minerals. Full-metal pads can have a metal content exceeding 70%, and some racing cars even use metal alloys as their base.

These brake pads are truly heat-resistant. Semi-metallic versions can withstand temperatures between 400 and 600°C, while full-metal versions are even more capable, exceeding 800°C. Even under continuous braking pressure, such as in racing or when a truck is pulling a heavy load, they maintain their power and resist wear. Full-metal brake pads for trucks can last for 80,000 to 100,000 kilometers and offer a strong load-carrying capacity.

However, they also have drawbacks. They wear the brake disc more aggressively, are prone to noise when braking, and offer less effective braking power during initial use in winter. They are also about 20% heavier than organic brake pads, potentially placing a strain on the vehicle's suspension.

Therefore, they are more suitable for vehicles like trucks, SUVs, and off-road vehicles that tow frequently or travel difficult terrain. They are also commonly used in racing and performance cars. For family cars that frequently travel mountain roads and long distances, semi-metallic pads are also a good choice.

Finally, ceramic-based pads are considered the "high-end" of brake pads. They primarily use ceramic fibers, along with resins and graphite. They contain virtually no metal, and any metal present is only minimally rust-resistant. This type of brake pad offers exceptional all-around performance, withstanding temperatures of 600-800°C (192-200°F) and resisting heat damage.

It also offers stable friction, a linear feel when braking, and produces only one-third the wear of metal pads. Family cars can expect 60,000-80,000 kilometers, with virtually no noise when braking and minimal dust generation, eliminating the need for frequent wheel cleaning.

However, it's not cheap, costing roughly two to three times as much as organic brake pads. Initially used in winter, braking response may be slightly slower than with organic pads, but this won't be noticeable in daily driving. Also, be aware that some cheaper ceramic brake pads are "fakes"—they simply contain ceramic powder and offer subpar performance. These pads are more suitable for mid- to high-end family cars, luxury sedans, and those who prioritize comfortable and stable braking.

Of course, choosing the right material isn't enough; regular use and maintenance are also crucial to ensure long-lasting and safer brake pads. Avoid frequent "hard braking" while driving. Frequent sudden or heavy braking can cause the brake pads to heat up rapidly, accelerating aging and potentially forming a "crust" on the surface, making them less effective. It's recommended to maintain a safe distance from the vehicle in front, check road conditions in advance, and use light or gentle braking to slow down.

Brake pad thickness should be checked regularly. Newly purchased brake pads for family cars are approximately 10 to 12 mm thick. If they wear down to 3 to 4 mm, they must be replaced. Otherwise, the metal base will directly rub against the brake disc, damaging it and significantly reducing braking power. An average family car should have its brakes inspected every 20,000 km or once a year. For cars that frequently drive on mountain roads or in congested urban areas, they should be inspected every 15,000 km.

After replacing new brake pads or discs, they should be run-in. Avoid sudden braking for the first 200 km, and drive at speeds below 60 km/h. For 200 to 500 km, you can apply a little more forceful braking, but not too aggressively. After 500 km, normal operation should resume.

Don't brake immediately after wading through water. Water can become trapped between the brake pads and discs. Once the brakes are applied, the water turns to steam, affecting your braking. Gently apply the brakes several times to evaporate the water using the heat generated by friction. Wait until the brake pedal feels normal before driving again.

When purchasing, choose brake pads that match your car model. Avoid low-quality, no-name brands. Choose reputable brands and tell them your car model. If you experience a squealing or metallic grinding sound when you apply the brakes, or if the brake pedal feels soft or the car veers when braking, check your brake pads immediately.

In short, choosing brake pads depends on your car's intended use and how you drive it. Paying careful attention to maintenance during regular use will ensure reliable braking. After all, brake pads are the last line of defense for driving safety, so don't neglect them!