Squeaking noise when braking once per wheel rotation

Question

I have a Hyundai Tucson 2016, and when I'm breaking, I hear some sort of a squeak sound that comes from the front left side of the car. It seems to occur once every full wheel rotation. So the faster the car goes when I'm starting to hit the brakes, the more I will hear the sound. And the slower the car goes, the less amount of times I will hear the sound (if that makes sense).

Since it appears to be happening based off wheel rotation, I'm not sure what it could be. I had bad brake pads in the past, and the noise that it produces usually happens as soon as I hit the brakes (a constant sound), not some sort of a rotation based noise. And since I cannot feel or hear anything when driving normally without hitting the brakes, I guess it's not related to anything other than the brakes.

Any ideas what it could be? My 2 guesses are the brake pads (haven't checked them yet) or the brake rotors (the rotor seems fine. Not an expert though). Thank you very much

Answer 1

The brake pads have a metal tab that makes contact with the rotor when the pads wear to the limit. Sometimes the squeal can be continuous, but not always. Sometimes it squeals like you describe. I would check your pads.

Answer 2

There might be some contaminant in your disc/drum that causes a squeal. I remember from years ago hearing about discs occasionally having deposits of harder or softer material that would cause this effect as the pad passes. Options: 1 - don't worry about it; 2 - replace the disc; 3 - apply a tiny amount of grease to the back of the pad and see if that helps.