It sounds like a siren. Bystanders turn and stare. Aside from the noise there are no ill effects, but I can stand it no longer. I don't want to wait until whatever it is finally breaks. I'm headed to the dealer because at 19,700 miles it's still under warranty.

The noise does not seem to be coming from the steering pump -- it doesn't change with steering load and it seems to be coming from higher up, near the top of the Pentastar 3.6-liter V6. My money is on alternator or the belt tensioner.