Where to Check Brake Pad Thickness?
3 Answers
Brake pad thickness can be observed through the wheel hub gap. Brake pads, also known as brake linings, refer to the friction materials fixed on the brake drum or brake disc that rotates with the wheel. When the friction materials are worn out, the brake pads should be replaced promptly. Otherwise, the steel plate will come into direct contact with the brake disc, resulting in loss of braking effectiveness and damage to the brake disc. Brake pads consist of a steel plate, an adhesive heat insulation layer, and a friction block. The steel plate is coated to prevent rust, while the heat insulation layer is made of non-heat-conductive materials to provide thermal insulation. The friction block is composed of friction materials and adhesives, which are pressed against the brake disc or brake drum during braking to generate friction, thereby achieving the purpose of vehicle deceleration and braking.
Every time I change tires or perform maintenance, I always check the brake pad thickness as a seasoned driver with over a decade of experience. Typically, I first remove the wheel and use a caliper to measure the thickness of the brake pad material. New pads are usually around 10 mm, and they should be replaced when worn down to less than 3 mm. If I don't remove the wheel, many cars have small holes or gaps in the wheel spokes where I can shine a flashlight to see the thickness markings or edges. The wear indicator is a built-in small metal piece that emits a screeching sound when the thickness is too low, reminding you to take timely action. Brake pads that are too thin can lead to reduced braking performance and increased risk of skidding in rain or snow. I make it a habit to check them every six months—it's both safe and cost-effective, avoiding the hassle of a breakdown on the road. Measuring them yourself is simple; all you need is a caliper, which costs just a few dollars.
Having worked in an auto repair shop for several years, I recommend regular brake pad thickness checks for average car owners. Most vehicle models feature inspection holes or small windows on the wheel hub side, allowing visual confirmation without wheel removal—just crouch down and use your phone's flashlight to illuminate. You can immediately see the exposed portion of the brake pad. When thickness falls below 3mm, material wears rapidly, increasing rotor damage risk; replacing them early prevents greater expenses. Designs vary by vehicle—for example, front-wheel-drive cars make front pads easier to inspect, while rear wheels may require repositioning the car. Safety first: poor braking performance extends stopping distances, creating highway hazards. I advise combining checks with routine maintenance—it's cost-effective and efficient. Gentle driving habits reduce wear, and using lower gears for deceleration helps prolong pad life.
