a noise is coming form a couple of my wheels when i brake. is it the brake pads are worn out? this happenned almost overnight though?

 

what car and describe the noise better..

 

that is the most vauge description for an automotive diagnosis i have ever heard...besides when i get a call from someone (hey my car is doing this thing, whats wrong with it)

 

lol. if its squeaking, it means you either have crappy pads, dust in your pads, or ur pads r low

if its likea a humming like resonating, that means your pads are rubbing against your breaks in such a manner that ur pads humm, thats normal becuase disks are allways rubbing the pads, they "float"

if its a surging with that humming, like it goes on and off seamingly as the wheels turn, ur probly have warped rotors. a way to test this is to get up to like 80 or 90 then gradually ease on the breaks form soft to somewhat hard and if u feel a vibration, medium-violent, then you most likley have warped rotoes. im in teh same boat as that buddy.