How to Determine When Car Brake Pads Need Replacement

[IsabelLynn]

Methods to check if car brake pads need replacement: 1. The vehicle dashboard has a brake pad wear limit warning light; generally, when this light comes on, it reminds the owner to replace the brake pads. 2. The thickness of brake pads is between 1 to 1.5 cm (may vary by manufacturer). When the wear thickness is less than 3 mm, the brake pads should be replaced promptly. 3. If there is brake caliper leakage, contaminating the brake pads and soaking into them, and oil stains are still found after sanding with sandpaper, the pads must be replaced regardless of thickness. 4. A decrease in brake fluid in the brake fluid reservoir. 5. Hearing a squeaking sound when braking is a reminder for the owner to replace the brake pads promptly.

[EmmaDella]

As an experienced DIY car maintenance enthusiast, my advice focuses on three key aspects: thickness, sound, and pedal feel. Use your phone's flashlight to check between the wheel spokes - if the brake pad thickness is below 3mm (about two coin thicknesses), it's time for replacement. If you hear sharp metallic scraping sounds (like squealing) when lightly braking, this means the wear indicator tabs are grinding against the rotor, which severely damages the disc. I learned this the hard way - delayed replacement cost me an extra 800 yuan for new rotors. Now, whenever I smell burning after continuous downhill driving or notice the brake pedal feels spongy requiring deeper depression, I know it's inspection time. City drivers should check every 50-60k km, while mountain road users need inspections every 30-40k km.

[Ian]

Last week, while helping my neighbor's daughter check her car, I noticed iron filings accumulating on the right rear wheel. This is actually quite easy to diagnose: by observing the brake pad thickness through the wheel hub gaps. New pads are about 1 cm thick, and they must be replaced when worn down to 3 mm. Hearing a harsh grinding noise means the wear indicator is activated, at which point you can drive at most another 200 kilometers. I taught her to feel the brakes with her foot—if the pedal vibrates severely or needs to be pressed very deeply to stop, these are both danger signals. I remember one car owner who ignored the squeaking noise and ended up with deep grooves worn into the brake discs, requiring expensive replacements.

[McEmilio]

The other day at the repair shop, I saw a car with 70,000 kilometers on it, and the brake pads were so thin they were almost transparent. Actually, daily inspection is quite simple: check the brake pads inside the wheel rims. If the wear indicator grooves disappear, it's a warning sign. Pay attention to the metallic scraping sound—that's the brake pad wear indicator scraping against the rotor. The pedal feel is also crucial. If you need to press the brake pedal hard to stop, it's extremely dangerous. Once on the highway, I noticed the braking distance had increased, so I immediately pulled into a service area to check. Sure enough, both front and rear brake pads were completely worn out. During maintenance, it's best to measure the thickness. If the front pads are below 3mm or the rear pads below 2mm, replace them immediately.

[LaKai]

Here are a few simple and practical inspection methods: 1. Regularly check the thickness through the wheel hub gaps—replace if it's thinner than a new smartphone. 2. Pay special attention to the 'squeaking' metal friction sound when driving with the window down; head to the repair shop immediately if you hear it. 3. Focus on changes in brake pedal feel—replace if it feels like stepping on cotton or if the car body shakes. Remember, last year a colleague ignored the warning sound and ended up gouging deep grooves into the brake discs during an emergency stop. Depending on driving habits, city driving requires a thorough inspection every 50,000 kilometers.

[Lawson]

This is how I check both of my family cars: every month after parking, I use a flashlight to quickly inspect all four wheels' brake pads for thickness. Nowadays, many cars come with warning systems - if you hear a 'squealing' noise, there's a 90% chance they need replacing. Pay attention to brake pedal travel while driving - if you find yourself having to press it all the way down to stop, that's extremely dangerous. Last week when driving a friend's car downhill, I clearly felt the brakes weren't holding; upon inspection, the pads were worn down to just 2mm, with the metal backing plates already sparking from friction. Always measure thickness during routine maintenance - front brake pads below 3mm must be replaced immediately, never wait until they're completely worn down and damage the brake discs.