Q: Knock sound while braking

asked by on September 12, 2016

I always hear a knock sound when I brake my car. The sound come out of the left wheel

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Hello. A knocking sound when braking is most likely from the brake pads moving inside the caliper bracket and the rotors having a warped surface causing the pad movement. The pads may be aftermarket and not fit tight enough in the caliper bracket. I would recommend having the pads replaced and the caliper brackets checked for wear on the pad contact surfaces and replace them if they are. Also replace the front rotors or have them resurfaced if they can be. If you would like to have this diagnosed for you, a certified technician from YourMechanic can inspect the brake system and let you know what repairs are needed.

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