I need some real professional help...Recently I installed a used p/s pump on my '92 745T as the old one was whining and growling as if it was low on fluid. The one just I installed, had been off a car for a while but stored indoors. It makes more noise than the other one. One Volvo shop listened with a stethscope and thought it might be an internal valve. I had a new p/s rack repalced three months ago and installed an in-line filter after flushing the old fluid out. Another shop said it may not be getting enough fluid so I removed the filter...Same loud p/s moaning. After I installed the pump, I did the, turn-it-full-right-then-full-left several times to remove any air and it's been driven 500 miles since....The sound increases when turning at slow speeds but seems to go away at higher speeds. Now Im wondering if the old pump really was bad and something might be inhibiting the flow of fluid. The resevoir level is correct and the fluid flows well. Power steering belt is new and pulley alignment is on. I added some p/s fluid with a conditioner and the fluid was compatible with what the shop used when the rack was replaced. At lower speeds, the sound changes with the speed of the engine. Whats next? By the way, the replacement pump had the same pulley diameter and all fittings were correct.