why brakes produce a noisy(crying) sound?

Take the car back to the mechanic and tell him to lubricate the area where the calipers contact the bracket with high temperature grease. Your brake pads are not retracting the tiny bit it takes to avoid dragging.

One of the things that's happening in the last few years is ever company has a lifetime brake pad that also generates almost no brake dust well to do that they made them ALOT harder and they are so hard that they can cause noise they also generate more heat which can cause that glazed look on your rotors etc. One of the easiest fixes is to replace the better pads with a cheaper pad that is actually a softer compound drawback is they won't last as long and they can leave the dust on you wheels etc.

i could say its the brake pads that should get replaced. A steel on steel sound in all likelihood does not be led to with the aid of undesirable rotors. If the wheel shakes once you ruin at intense velocity, your rotors are warped and could be machined down or replaced.

Same thing happened to me. Just take it the mechanic and they should fix it. If you do not fix it your brakes will catch on fire when driving down the road.

You should buy brake pads and if that dont work then it might be the pistons

It should be under warranty. do what the mechanic said.

don,t fool with it. that car should still have the warranty. let them figure it out.