Hi. I just suffered the same symptoms on my '84: stiff steering (intermittant power assist, none in the first cold of the morning, getting better as things warm up) with the onset of cold weather (here in the northeast). My final solution, however, might be your solution as well.

First, I flushed out the fluid and replaced it with AmsOil synthetic ATF (ATF is what is called for in the '84's owners manual), and I had it on hand because I used AmsOil in my tranny. But although the original fluid was brown, the new cherry red fluid didn't help.

[This doesn't apply to you, but read anyway] Then I figured the belt was slipping -- and there are two belts involved -- the crank-to-A/C belt, and the A/C-to-P/S belt. So I got the IPD conversion kit to bypass the first belt (my 25-yr old A/C doesn't work anymore, anyway) and now have a single belt running directly from the crank pulley to the P/S pump. That didn't help much, either. [and the kit can't be installed on '85-on cars, anyway].

But the next, last step fixed it! The belts, both before and after the aforementioned conversion, felt tight, but I know that feeling the belt when still isn't necessarily the same tension when running because the accessory bushings (still original and 25 years old) could be flexing -- and thus allowing the belt to slip, albeit it quietly -- under load. So I changed the four bushings (in the '84 -- I don't know how many bushings are in your '89) with IPD's blue, polyurethane bushings. I've put this type in my other cars, for the alternator, for example, and I like their extra rigidity and long life (resistant to oil, too). Anyway, it took just a couple of hours*, and the power steering works fine now. All fixed.

Hope this suggestion, changing the bushings, work for you, too. It's cheaper and easier than getting a replacement steering rack or pump.

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* Here's a suggestion for installing the poly bushings. While the old rubber bushings came out easily (showing how soft they had become), it's hard to get the new poly's in. So I got a short bolt (1/4 inch diameter), with washers wider than the inner diameter of the metal loops the bushings slide into, and turned the nut-bolt to pull the bushings into the loops. It's slow (which is why the whole job took a couple of hours) but really easy this way.

Good luck.

Hi there,

You don't mention the U-joints. I'd jack up the front (both wheels) and run it lock to lock with and with the motor running, just to be absolutely certain it is not dried up U-joint bearings before getting into the hydraulics.
--
Art Benstein near Baltimore

When an actress saw her first strands of gray hair she thought she'd dye.