The replacement of vehicle brake pads is the most important stage in automobile maintenance. The brake pads endanger the quality of the brake pedal, which is related to the safety of travel. The replacement of damaged brake pads seems to be very important. When it is found that the brake pads are worn and need to be replaced, a friend asks if four brake pads should be replaced together? In fact, it is generally not necessary to replace them together.

The wear degree and service life of the front and rear brake pads are different in many cases. Under normal driving conditions, the braking force received by the front brake pads will be relatively large, and the degree of wear and tear will often be greater, and the service life will be shorter. It needs to be replaced at about 30,000 to 50,000 kilometers; the rear brake pads bear less braking force and can be used for a longer time. Generally, they need to be replaced at 60,000 to 100,000 kilometers. When dismantling and replacing, the coaxial ones must be returned together, so that the braking force on both sides will be balanced. If the front and rear left and right brake pads are worn to a certain extent, they can also be replaced at the same time.

Brake pedals can not be changed alone, it is better to change a pair. If all is used up, you can consider replacing four. Everything is normal. The front two are replaced together, and the latter two are returned together. You can also replace the front, back, left, and right.

Car brake pads are generally replaced once every 50,000 kilometers, and the brake shoes are checked once every 5,000 kilometers of driving. Not only the excess thickness should be checked, but also the damage of the brake shoes. Is the level of damage on both sides the same, return to the original position Is it easy to wait and find an abnormal situation that needs to be resolved immediately.

So, when exactly should the brake pads be replaced? How to carry out the brake pad self-test?

The thickness of a new brake pad is generally about 1.5cm, and the thickness will gradually become thinner with the continuous friction in use. Professional technicians suggest that when the thickness of the brake pads is only about 1/3 of the original thickness (about 0.5cm), the owner should increase the frequency of self-inspection and be ready to replace it at any time. Of course, due to the design of the wheel hub, some models do not have the conditions for visual inspection, and the tires need to be removed to complete.

There is a raised mark on both sides of each brake pad. The thickness of this mark is about two or three millimeters. This is also the limit for the thinnest replacement of the brake disc. If the thickness of the brake pad is already parallel to this mark, it must be replaced.

Therefore, when the thickness of the brake pads is close to this mark, the car owner must observe and prepare at any time, but it is difficult to observe accurately with the naked eye without removing the tires. Prompted, relatively self-test is more convenient.

Small suggestion: There is no strict replacement interval for the brake pads according to the vehicle environment and driving habits. Generally, it is necessary to consider replacing the brake pads after driving about 60,000 kilometers. When it is found that the brake pads are thin by visual observation, a technician should be asked to check during maintenance, because there will be errors in visual observation, and professional maintenance stations pass calipers more rigorously than visual observation.

If there is a sound of "iron rubbing iron" when you tap the brakes (it may also be the effect of the brake pads running in at the beginning of installation), the brake pads must be replaced immediately.

Because the limit marks on both sides of the brake pads have directly rubbed the brake disc, it proves that the brake pads have exceeded the limit. In this case, when replacing the brake pads, it is necessary to cooperate with the inspection of the brake disc. When this kind of sound occurs, the brake disc is often damaged. In severe cases, the brake disc needs to be replaced.

In addition, some poor-quality brake pads have hard spots, which will also produce abnormal noise. Generally, the abnormal noise generated will disappear after a period of wear.

Small suggestion: When you hear the sound of the brakes, it is often too late, and the brake disc will be damaged more or less at this time. The price of brake discs is much higher than that of brake pads, so it is recommended that you check the brake pads frequently to avoid damage to the brake discs.

If the brakes feel very hard, it may be that the brake pads have basically lost their friction and must be replaced at this time, otherwise a serious accident will occur.

Small suggestion: This method is relatively abstract, and it may be difficult to grasp by feeling, so it is very important to develop a good self-examination habit. In addition, the reduced braking effect will increase the consumption of brake oil, so when replacing the brake pads, it is necessary to focus on checking the condition of the brake oil.