I have 1993 toyota V6 extended cab. The power steering pump went out, and I have put several new (reconditioned) pumps on. It stills whines and the assist goes on and off. Mostly no assist. Anybody have any ideas. I was told that the high pressure line might have a restriction... Anything to this. I believe the assembly is roughly $70.

Replace your box too. You could also try some Lucas' power steering fluid, it really helps my steering box with the 37" swampers on my FJ40.

Use Dexron III automatic transmission fluid, never auto parts store "power steering fluids" or additives. Read and follow the power steering fluid bleeding procedure in the factory manual. The high pressure hose never needs to be replaced unless it's obviously leaking (the hose commonly last 20-40 years in unmodified cars and trucks)

My power steering pump is about dead on my truck too. I am going to replace it soon.