The only time I changed the power steering fluid on a brick was when I replaced a rack on my old '87 244.The PS fluid in my 3 cars was black so I changed it even though Volvo states "no fluid change required".What a difference,feels like I have a new rack in all three cars.
I got this pump a few years ago from JC Whitney for oil changes because the drain plug bolt was stripped on my '67 122.This thing has come in pretty handy,it took only seconds to suck all the old fluid out.I refilled it drove for a bit and changed that fluid.Now my bricks and the SAAB story have brght red PS fluid.No more morning stiffness.
Volvo should recommend changing the PS fluid, maybe every 60,000 miles.
Same goes for the rear differential and manual transmissions.I recommend changing those fluids too.
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philvo '86 245 215k,'90 240 196k,'87 SAAB 900 SPG 213k