I know there have been a few additives posted here that will quiet down a noisy power steering pump. I would just like to add one more to the list. Lucas Power Steering Additive also does the trick. I couldn't find the other products locally, so the guys at NAPA said I should use this stuff. It works great. I poured half a bottle in the reservoir and the pump shut up before I was out of the parking lot. This thing was so loud it would drive you nuts. Just thought I'd share the info. BTW, the bottle was just over $8 including tax.
Chris