I would not hesitate to use the Lucas power steering product. I have used it and think it does its job admirably.
However, if you live in a place where it gets cold, you'll find that it's too thick to leave in there over the winter. Once the car gets going it's fine, but when you first start the car up and you're trying to maneuver out of the parking lot you will find the steering TOO STIFF - as if you don't have any power assist. This also seems like it creates a pretty tough situation for the pump.
Put replace the fluid in the reservoir with the Lucas product and then before it starts to get cold, do a full flush with a fully synthetic ATF and you should have no problems.
Of course, I can't guarantee that the Lucas power steering product will fix your problem, but it's worth a shot right?
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1998 V70 AWD->FWD Turbo 200k+
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