I have an '03 quad cab 4.7 with 45RFE tranny. I have developed a noise from somewhere under the hood. It sounds just like a power steering pump whine, it changes with the RPM up or down. Does not have to be in gear. I thought maybe transmission, but I removed the belt and ran cold for a minute and the noise went away. My thought was power steering pump, so I replaced it, and the noise is still there. Any help would be much appreciated.

 

idler pulley?