As for as your brakes go, never put any grease or lubricant near the pads or rotors! There is a possibility that there may be a small stone or dirt stuck between the pads and rotors try reversing in a safe area, at a faster than normal speed and applying brakes harder than usual this should clear out any debris. Is there any abnormal lines grooved into the rotor? Past a pic if your not sure? CHECK INSIDE AND OUTSIDE OF ROTOR. hop