How to Check the Wear Level of Brake Pads?
3 Answers
Check the wear level of brake pads as follows: 1. Check the thickness of the friction material: Brake pads consist of two parts: a metal base plate and a friction material. When braking, the friction material contacts the brake disc to generate friction, which provides the braking effect. The thickness of the friction material is usually 10 millimeters. When it wears down to 5 millimeters, it indicates severe wear, and the brake pads need to be replaced. 2. Listen for unusual noises during braking: Some brake pads have a hidden metal pin inside the friction material. When the friction material wears down to a certain level, the metal pin contacts the brake disc, producing a sharp, unusual noise during braking, alerting the driver to replace the brake pads. 3. Inspect the thickness of the brake pads: Remove the tire to clearly see the condition of the brake pads. Brake pads gradually wear down during use and must be replaced when they reach the wear limit.
The method I use most often is squatting down to check the brake pad thickness. New brake pads are about 12 millimeters thick, and if they're worn down to around 3 millimeters, it's really time to replace them. The easiest way is to ask the car wash staff to take a quick look while washing your car—they usually use a small tool with a mirror to measure the thickness directly. Some cars have a brake pad warning light on the dashboard; if it lights up, it means the wear limit has been reached. The most intuitive method is listening for sounds—if you hear a metallic squeaking noise when lightly braking, it's likely the wear indicator signaling an issue. If you don't have any tools and are worried, try testing the brake pedal feel at low speed. If it feels spongy or requires deep pressing to stop, it could also mean the brake pads are too thin, reducing braking power.
Here's a practical trick for you: No need to remove the tire. Just shine a strong flashlight into the wheel hub gap. The brake pads are sandwiched between the brake disc and caliper, allowing you to see the thickness of the rubber layer on the metal clip. Generally, if the rubber layer is thinner than a coin's edge, it's dangerous. Some high-end cars display brake pad lifespan percentage directly on the dashboard. I make it a habit to check whenever I change tires – repair shops use specialized calipers for precise measurements. If you're feeling lazy, monitor the brake dust situation. A sudden increase in black dust on the wheel hub indicates accelerated wear. Recommended to check every six months, especially for frequent highway drivers.