I have a '99 Chevy Lumina 3100 V6 with 54k miles. There is a high-pitch buzzy whine that changes pitch with engine RPM/transmission speed. I removed the serpentine belt and drove it briefly - the noise is still there without the belt. So it's not the power steering pump, alternator, H20 pump or belt tensioner. Transmission has had regular service (fluid is full and clean) and shifts smoothly in all gears. The noise is only evident while moving (forward or reverse) above 5 mph. There is a slight raspy "scraping" noise in park or neutral, which becomes almost undetectable when shifting to drive or reverse with the brake still applied.
Thursday, November 8th, 2012 AT 4:27 PM