Must Brake Discs with Grooves Be Replaced?
2 Answers
Brake discs with grooves must be replaced. Causes of brake disc wear: 1. Inferior quality brake discs or drums can lead to premature wear of brake pads; 2. Damage to the brake calipers in the braking system over long-term use can cause the brakes to not release properly; 3. The materials used for the brake discs do not meet requirements, or the friction layer design density of the brake discs is unreasonable; 4. The original brake pads have a small design area, and are used under conditions of long-term overspeeding, frequent braking, overloading, and prolonged high temperatures. When the driver presses the brake pedal, the brake calipers clamp the brake discs to generate braking force, slowing down or stopping the vehicle. The braking system mainly consists of a vacuum booster pump, master brake cylinder, wheel brake cylinders, brake pads, and brake discs.
I've been driving for 20 years and encountered brake disc grooves a few times. Honestly, replacement isn't always necessary. Grooves are those small channels on the disc surface, usually caused by uneven brake pad wear. If the grooves are shallow—say, only 1mm deep—and the car still drives fine with decent braking, there's no rush to replace them. Just have a repair shop resurface the discs; it's cost-effective and eco-friendly. However, if the grooves are deep (over 1.5mm) or the brakes vibrate noticeably while driving, replacement is mandatory. Otherwise, braking distance increases, and the risk of skidding in rain becomes too great—not worth saving a few hundred bucks. I recommend regularly checking brake pad thickness. If grooves reappear after installing new pads, it might indicate disc warping or installation issues, warranting thorough inspection. Remember: safety is non-negotiable. Don't gamble with minor issues—have mechanics inspect disc surfaces during every maintenance check.
