These abnormal noises are various reasons. Now, we can sort out and share them with you. I hope that these annoying brake system noises will no longer annoy the maintenance colleagues, nor let the owners get upset. They will no longer make these problems the reason and excuse for the owners to tease our maintenance colleagues that "one brake abnormal noise is not good...".
First, you should distinguish between the abnormal sound, whether it is screaming, or dull, or silk. Scream. First, check that the brake pads are running out (the alarm pads sound).
If it is a new one, check whether the brake disc and the pad are in good agreement.
Dull noise is a problem with brake callipers, such as wear of movable pin, falling off of spring plate, etc. Silk, the problem is more, calipers, brake discs, brake pads may have problems.
If the brake is continuously sounded, first, check whether there is a drag brake, and the poor reset of the caliper will cause friction between the disc and the disc for a long time. It is necessary to see whether the brake disc has groove, because local friction will cause abnormal noise. If the disc is OK, consider whether the brake pads are too hard or the pads are installed incorrectly.
The mechanism of brake noise
The mechanism of brake scream is caused by self-excited vibration. The friction excitation between the brake disc and friction material provides energy for the whole brake system, which is transmitted between the whole brake assembly and the connected suspension and chassis parts and produces vibration response. The system vibration with high amplitude will be produced when the brake scream occurs.
The main influencing factors of braking noise are as follows
(1) Brake pad, friction pad material, friction pad structure, friction coefficient, caliper compressibility, damping pad, friction material chamfering, steel back dimension tolerance structure;
(2) Material and structure of brake disc;
(3) The structure of the brake caliper bracket and the structure of the brake caliper shell;
(4) Material and structure of knuckle, bearing and wheel bracket;
The above products that do not meet the requirements will produce braking noise. Take Audi as an example
Classification of abnormal braking noise of Audi
Abnormal brake sound caused by damage of front brake caliper stop spring:
Description of abnormal noise: creak, rattle, rattle, clatter, clatter, clatter, metal knock in the front wheel area when stepping on the brake or driving on uneven road
Main models: Audi
Cause: the front brake caliper stop spring is broken
Maintenance method: replace the front axle left and right brake caliper stop spring at the same time
(1) Brake pad, friction pad material, friction pad structure, friction coefficient, caliper compressibility, damping pad, friction material chamfering, steel back dimension tolerance structure;
(2) Material and structure of brake disc;
(3) The structure of the brake caliper bracket and the structure of the brake caliper shell;
(4) Material and structure of knuckle, bearing and wheel bracket;
The above products that do not meet the requirements will produce braking noise. Take Audi as an example
Classification of abnormal braking noise of Audi
Abnormal brake sound caused by damage of front brake caliper stop spring:
Description of abnormal noise: creak, rattle, rattle, clatter, clatter, clatter, metal knock in the front wheel area when stepping on the brake or driving on uneven road
Main models: Audi
Cause: the front brake caliper stop spring is broken
Maintenance method: replace the front axle left and right brake caliper stop spring at the same time
