On urban roads, traffic lights and congested roads make frequent vehicle starts and stops a norm. Under such driving conditions, car brake pads need to continuously rub against the brake disc to generate braking force, causing their wear rate to far exceed that of normal driving scenarios. From a mechanical point of view, each time the car brake pads are braked, they are tightly fitted to the brake disc under the push of hydraulic or air pressure, and the huge friction forces the wheels to slow down until they stop. Frequent friction work not only generates a lot of heat, but also aggravates the wear of the surface material of the car brake pads, causing the thickness of the car brake pads to gradually become thinner. This is the core reason for the wear of car brake pads under urban driving conditions.
During initial use, new car brake pads and the surface of the brake disc need to go through a certain period of running-in. The wear in this stage is relatively fast, which is a normal "running-in period wear". Usually after driving 500-1000 kilometers, the fit between the two is improved and the wear rate tends to be stable. As the mileage increases, it enters the "stable wear period". During this stage, if the driving habits are stable, the car brake pads wear relatively evenly, and the thickness of the car brake pads will decrease by 0.5-1 mm for about every 1000-1500 kilometers. However, when the thickness of the car brake pads approaches the limit value specified by the manufacturer (generally 2-3 mm), it enters the "accelerated wear period". At this time, the friction material performance of the car brake pads decreases, the wear rate is significantly accelerated, and the braking performance is also affected, and it needs to be replaced in time.
From the material characteristics of car brake pads, different types of car brake pads have different wear patterns in urban driving. Semi-metallic car brake pads contain more metal fibers. Although the braking force is strong, in the high temperature environment of frequent start-stop, the metal components are prone to violent friction with the brake disc, resulting in increased wear, and the generated metal debris may also scratch the brake disc, shortening the service life of both. Ceramic car brake pads, with good high temperature resistance and low friction coefficient, show better wear resistance in urban driving, and their wear rate is relatively slow, but the price is relatively high. Although organic car brake pads have low noise and low cost, they have poor high temperature and wear resistance. They wear out the fastest and have the shortest service life under urban driving conditions.
Frequent starting and stopping can also cause uneven wear of car brake pads. In urban driving, the center of gravity shift during vehicle braking and the uneven force on different wheels will cause the front car brake pads to wear out significantly faster than the rear car brake pads. Usually, the replacement cycle of the front car brake pads is 20% - 30% shorter than that of the rear car brake pads. In addition, if there are problems with the vehicle suspension system or inconsistent tire pressure, the two car brake pads on the same axle will also wear to different degrees. In severe cases, it may even affect the vehicle's braking balance and increase safety hazards.
In view of the wear characteristics of car brake pads under urban driving conditions, regular inspection is the key maintenance point. Car owners should observe the thickness of the car brake pads every 1-2 months or every 1,000 kilometers. If the thickness of the car brake pads is found to be close to the wear limit, they should go to a professional repair shop for inspection in time. Professional maintenance personnel will measure the thickness of the car brake pads with a caliper and use professional equipment to detect the flatness and wear of the brake disc to determine whether the car brake pads need to be replaced or the brake system needs to be maintained.
Reasonable driving habits can also effectively reduce the loss of car brake pads. In urban driving, predict the road conditions in advance, avoid sudden braking, and reduce the frequency of using car brake pads by releasing the accelerator and using the engine drag effect to slow down. When following a car, keep a safe distance and smoothly control the braking force according to the speed change of the car in front, which can not only improve driving comfort, but also reduce the wear of car brake pads. In addition, regularly perform vehicle maintenance, check the brake fluid level and quality, ensure that the brake system pipeline is leak-free and unblocked, ensure the normal operation of the brake system, and indirectly extend the service life of car brake pads.
When the vehicle is found to have abnormal brake noise, longer braking distance, abnormal brake pedal travel, etc., it should be stopped immediately to check the status of the car brake pads. These phenomena may be caused by excessive wear of the car brake pads, cracks on the surface, or foreign matter embedded in the car brake pads. If not handled in time, it will not only accelerate the wear of the car brake pads, but also cause serious traffic accidents. Timely replacement of severely worn car brake pads and comprehensive maintenance of the brake system can ensure that the vehicle always maintains good braking performance and ensures driving safety in frequent start-stop city driving.
