Ever since I bought my TrailBlazer in '06 I've heard this annoying whine at low speeds. It may make it at higher ones too, if so the road noise is drowning it out. It doesn't seem to get any worse. I figured it was the transmission, since it's only heard when the car is moving, but when I got a leak in the power steering system I found the whine from the power steering pump was exactly the same. I'm guessing that replacing the power steering pump will eliminate this noise, but I'm not sure.

I really don't like that noise, but I'm not going to put money into it either. If it aint broke I aint gonna fix it.