Do I Need to Replace Brake Pads When Changing Brake Discs?
3 Answers
It is not necessary to replace the brake pads together. Brake pads, also known as brake linings, vary in material depending on the brand and price range. Some are made of ceramic, others of metal, and higher-end ones even use carbon fiber. Besides materials, there are significant differences in the composition and performance of brake pads. Brake pads are installed inside the brake calipers and are the most critical safety components in a vehicle's braking system. The effectiveness of braking is determined by the brake pads, which generally consist of a steel plate, an adhesive heat-insulating layer, and a friction block. Of course, different brands make modifications based on this. For example, Lishida brake pads excel in noise reduction, utilizing a three-layer soundproofing system, precision-stamped steel backplates, imported raw materials, and original noise reduction techniques to solve noise issues during braking. When the brake pedal is pressed, the brake pads are squeezed against the brake disc, generating significant friction to achieve vehicle deceleration and stopping. Brake discs, also known as brake rotors, are disc-shaped metal components. There are various types of brake discs, including drilled, slotted, standard, and ceramic composite types. During driving, the brake disc rotates with the tire. Similar to the brake pads, when the brake is applied, the brake pads press against the brake disc, creating substantial friction to slow down or stop the vehicle. Brake discs offer better braking performance and are easier to maintain compared to drum brakes. Conditions for replacing brake discs include: Check the thickness of the brake disc: Most brake disc products have wear indicators. If the total wear depth on both sides reaches 3mm, the brake disc should be replaced promptly. Check the wear level of the brake disc: If the wear is minimal shortly after replacement, there is no need to replace it. Generally, brake discs should be replaced every three brake pad changes, but this is not a strict rule. It also depends on how frequently the driver uses the brakes. Regular inspection of the braking system is recommended, and any issues should prompt immediate replacement. Check the usage cycle: Brake discs have a longer replacement cycle than brake pads. Under normal driving conditions, front brake pads need replacement every 30,000-50,000 kilometers, while rear brake pads require replacement every 60,000-80,000 kilometers. Front brake discs should be replaced every 60,000-80,000 kilometers, and rear brake discs every 100,000 kilometers or so.
I've been driving for over a decade, and it's usually recommended to replace brake pads when changing brake rotors. Brake pads are friction materials that work in tandem with the rotors; new rotors have smooth surfaces, and if the old pads are worn or uneven, they can scratch the new rotors, leading to unstable braking or loud noises. Once, I tried to save money by only replacing the rotors, but the old pads were still in use. Within two months, the braking performance deteriorated, and I ended up spending more time and money on repairs—more hassle than replacing both at once. In the long run, replacing both saves time and money while ensuring the braking system works efficiently. During regular maintenance, I always check the wear on both components. If the pads are still thick and haven't reached their limit, they might not need replacement, but this is rare—brake pads often wear out at the same time as the rotors. Safety comes first, so I insist on replacing both to ensure worry-free driving.
As a car enthusiast who frequently tinkers with vehicles, I believe that replacing new brake discs should be accompanied by new brake pads. In the braking system, the disc and pad are like partners—pairing a new disc with old pads can easily lead to issues: old pads may have irregular wear, causing grooves or thermal deformation in the new disc, increasing the risk of shaking or delayed braking. I've seen cases in modifications where replacing only the disc resulted in longer braking distances because the old pad material didn't properly bed in with the new surface, affecting friction performance. From a technical standpoint, replacing both ensures even force distribution and avoids hidden risks. Cost-wise, while it may require more upfront spending, it extends the lifespan of the new disc and reduces the need for repairs. I'd recommend checking the pad thickness to decide; if the pads are already worn down by more than half, it's more cost-effective to replace both. Maintaining system consistency is key—I've personally tested this method, and it makes braking more responsive and stable.
