shin2max

I don't really know what is wrong, about three months ago there was a strange noise coming from my passenger wheel when braking. It sounds like my pads are out like the metal is griding the rotors. After pressing the brakes a couple times it stop making the noise. But everytime I come to a stop, pressing the brake seems to sound the grinding noise. After I got home I checked the brake pads and it was fine the rotor and everything under the wheel was free from grinding the brakes or rotors. I continued on to test drive it and it came back on I try the emergency brakes when driving and it also sounds like a grinding too. What could it be?? I did a oil change and the noise went away for like two months, now it's back on and driving me crazy I don't know what is causing it. My ABS light is not on and so my brake pads are not worn out yet too. Can anyone help me figure this problem out.