Most commonly this is caused by a combination of things. A warped rotor will cause the caliper to slide back and forth on its mount once per wheel revolution. Grooves worn into the mounting surface the pads rest on cause them to click as they slide back and forth. Those grooves are caused by wear when the spacial brake grease is not used during a routine brake job, mostly by do-it-yourselfers. The clicking can occur only during brake application or it can stop occurring only during application. Both are solved by replacing or machining the rotors, and addressing the worn areas on the mounts.
There are other potential causes of a clicking noise, but they are usually not affected by applying the brakes. The splash shield behind the rotor can be bent and rubbing on the rotor. A wheel weight can rub against the lower spring plate on a strut. The crimp on the band on an outer CV joint can hit against the spindle, but that will usually wear down in time.
Rear brakes make clicking noises too when the drum is egg-shaped. That makes the shoes slide back and forth which can cause a clicking or a squeaking noise.
Thursday, February 9th, 2017 AT 3:15 PM