What Causes Vibration When Braking?
The reason why the vehicle-steering wheel vibrates when the brake is pressed is because the brake disc surfaces wear over time and turn into a curved (wavy) form. The reason for the bending of the brake disc, (wavy-conical) surface formation, friction with the lining, wear, temperature effect. In this case, the wear of the disc should be checked, if the amount of wear of the disc is not high, the surface of the disc can be smoothed by grinding the disc with the grinder, if the disc is very worn, that is, if it has completed its life, it should be replaced with a new one. The same process applies to drum brakes, brake drums are also corrected by grinding. If you change the brake pads without grinding or replacing them when there is a lot of fluctuating wear on the disc or drum, this noise will reappear, it should be noted. After the disc is grinded or replaced and the pads are renewed, it may make very little noise for a while, this noise will pass when the pad and disc get used to each other.
(Irregularly worn brake disc with curved surface, must be ground)
What causes the noise when braking?
If there is a high-pitched squealing sound when you press the brake pedal, if this sound is a loud metallic sound, your pads are finished. In some vehicles the brake pads have a metal tab that is shorter than the pad instead of the wear sensor, when the pad wear exceeds the limit value, this claw rubs against the disc and makes a noise, the driver will understand that the pad is gone and the pads should be changed as soon as possible. Using it this way for a long time will scratch the disc as the metal rubs against the metal, it may cost more. In most cases, even though the pads are new or unfinished, there is a noise when you braking, this is due to reasons such as hardening, dusting and contamination of the pad surface. In such a case, generally cleaning the pads with pad spray and compressed air will reduce the noise. If your brake is holding and the noise is not excessive, you can continue to use it, or have it serviced.If you have the materials even you can clean by yourself.
(Damaged brake disc shapes)
When to chance brake pads?
New generation vehicles have a pad wear sensor, when the pad is exhausted, the red brake light turns on in the driver's instrument panel, in this case the pad is replaced.
(Picture shows new and worn pad, wear limit.)