Auto Brake Pads: Guide & Tips

Automotive brake pads typically consist of three parts: a backing plate, a friction material layer, and a thermal insulation layer. The backing plate, typically made of steel, primarily secures the brake pad and evenly transmits braking pressure to the friction material.

The friction material layer is the core of braking performance, generating friction through direct contact with the brake disc. The quality of its material directly determines braking performance and service life.

The thermal insulation layer effectively blocks the high temperatures generated during braking, preventing heat transfer to the brake cylinder and preventing hydraulic fluid deterioration due to high temperatures, thereby ensuring the stability of the braking system.

Based on the friction material, brake pads currently on the market fall into three main categories. Resin-based brake pads are the most widely used type. They use resin as a binder and are mixed with materials such as metal fibers, ceramic fibers, and graphite.

This type of brake pad offers low cost, low braking noise, and minimal wear on the brake disc, making it suitable for everyday commuting vehicles like family sedans. However, they are relatively less stable in high-temperature environments. Metal-based brake pads contain a higher proportion of metal particles, including copper, iron, and steel.

They offer excellent high-temperature resistance and stable braking performance, making them suitable for high-performance vehicles or vehicles frequently operating in mountainous areas or on steep slopes. However, their drawbacks include loud braking noise and relatively severe wear on the brake discs.

Ceramic-based brake pads, a high-end product that has recently gained popularity, are primarily made of ceramic fiber and combine the advantages of both resin-based and metal-based brake pads. They offer stable braking performance, high-temperature resistance, and low wear, while also effectively reducing braking noise and being more disc-friendly. However, they are relatively expensive and are primarily used in mid- to high-end vehicles.

Brake pads are highly consumable components, and their lifespan varies significantly depending on factors such as driving habits, road conditions, and vehicle weight. Generally speaking, the lifespan of brake pads for family cars ranges from 30,000 to 80,000 kilometers, but the specific lifespan depends on the vehicle's specific conditions. Here are some common ways to determine whether brake pads need replacement:

First, observe the thickness of the brake pads. Most brake pads have wear limit markings on the backing plate. When the friction material layer wears down to the level of the markings (usually 3-5 mm), they must be replaced. Some models have transparent wheel hubs, allowing drivers to directly observe the brake pad thickness through the gap in the hub. If direct inspection is not possible, use specialized tools or have the brake pad inspected by a repair shop.

Secondly, pay attention to any abnormalities during braking. If you experience a harsh metallic grinding sound during braking (this may be due to the friction material being worn out and the backing plate making direct contact with the brake disc), a soft feel or increased travel on the brake pedal, or the vehicle swerving during braking, these could be signs of severe brake pad wear or a malfunction and require immediate inspection and attention.

In addition, some models are equipped with a brake pad wear warning system. When the brake pads are worn to a certain level, a corresponding warning light will illuminate on the instrument panel, reminding the driver to replace them immediately.

When replacing brake pads, there are a few things to pay special attention to. First, it's important to select brake pads that match your vehicle model. Different models have different brake pad sizes, installation methods, and friction coefficient requirements. Improper installation can lead to serious consequences, including brake failure.

Second, it's recommended to replace both brake pads simultaneously to ensure even braking on both sides and prevent the vehicle from swerving during braking.

Third, after replacing brake pads, a run-in period is required. During the initial period (usually 200-300 kilometers), avoid sudden or heavy braking to allow the pads and discs to gradually adapt and achieve optimal braking performance.

Fourth, when replacing brake pads, check the disc for wear. If the disc surface shows severe scratches, grooves, or excessive wear (thickness below the standard), it should be replaced promptly. Otherwise, the brake pads' braking performance and service life will be affected.