Just replaced the alternator mount bushings and tensioner bushings because they were totally shot. But the sound is still there. It is a harmonic rattle/vibration at 2500rpms to 3000rpms its not as loud but still there.My friend thinks it is the alternator pully/alternator that is bad. what do you guys think? has anyone else heard a weird harmonic vibration like metal on metal or a loose bolt or something. I took it to a shop and had him listen to it. I poped the hood and held the throttle cable down until hearing it. he thought it was the bushings. so... any help would be excellent!