2002 3.5 Engine Grinding at 3000 rpm

I just purchased a 2002 3.5 olds aurora and now when I drive the car and throttle the gas to 3000 rpm there is a metal on metal noise that i hear, almost like the brake checks are grinding on the rotors. It wont grind when not in gear only when im driving. I turn on the A/C and the noise is louder and different sounding. I had the front end looked at and everything is very tight. The serp belt is new, could this be a water pump ready to fail, alt, or ac clutch?????

I just purchased a 2002 3.5 olds aurora and now when I drive the car and throttle the gas to 3000 rpm there is a metal on metal noise that i hear, almost like the brake checks are grinding on the rotors. It wont grind when not in gear only when im driving. I turn on the A/C and the noise is louder and different sounding. I had the front end looked at and everything is very tight. The serp belt is new, could this be a water pump ready to fail, alt, or ac clutch?????

I just need to clarify something. Is the noise present when you are at a stop with the car in park? Or is it just present when the car is moving? Can you generate the noise if you put the car in neutral and give it gas? You may or may have not rad all my posts about my 2002 3.5 in the past. It's really easy to pull the seperentine belt off and check the bearings of the water pump, steering pump, ect. I spent 50 dollars for a new pump. It's really easy to change once you have the proper tools. Let me know what you plan to do. I have a subscription to alldata and as such have access to all the GM documents and schematics for this car. I would be more than happy to send you whatever you need.