I've had a dry front crank seal squeal like a banshee before. Spray some WD40 behind the balancer and see if it affects anything.
Interesting, that could very well be it, as it sounds like its coming from the crank pulley. Did that solve the issue for you, or was that just to see if that was the problem, with some other more intensive fix?
i wonder about the amount of oil in the pan or the conditoion of the pump. i had an oil poump let go and stop pumping aftwr 200k. pressure went to zero. it made weird noises.
I just did an oil change on it today, still made the squeal after. I don't think my oil pressure is that low. At least I hope it's not. I do not have a gauge, but the light does not ever come on. The engine only has 122,000 miles on it.
Just another thought, would a bad harmonic balancer cause this kind of noise?