As I replaced the PS tie rod I grabbed my upper A arm and could move it back and fourth easily by hand. It didn't do that when I replaced the brake lines 16 months ago but I have put 7000 miles on the car since then.

Ok next weekend I replace the upper bushings on both sides with IPd polly's and upper ball joint on the PS for good measure. It is an easy job when you have done it before. In any case the upper ball joint was probably ok but by the time I figured that out I had damaged the bellows. The lowers are more recent but not changed by me.

If the image works you can see how worn the bushing were by the time they were replaced. I attributed some of the shaking to the worsening tie rod but I'll bet I was feeling some slop up top.

From 2011-10-30 (by Eye-Fi)

Recommendations are a good thing. I would call the shops you've been referred to and feel them out. Make sure they have appropriate shims for the upper A-arm adjustments, and tell them in advance exactly what you've done, and why you want an alignment...

Make sure they don't just pull the steering wheel and put it back on straight.

When your alignment is finished and you are satisfied, Double check those upper A arm bolts. I've had shops not tighten those bolts enough, and had the shims fall out...

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-Matt I ♥ my ♂

I had my alignment done several months ago and it really helped lighten up the steering effort. Cost me less than a hundred dollars at my local independent Volvo shop. If at all possible you want this done by someone who is familiar with the quirks of the 1800.
Bob
66S

I replaced my tie rod ends and did a toe-in alignment myself using a jig to measure fairly accurately the distance between the front and rear of the tires. Seemed t work fine. Then I replaced upper A-arm bushings and got new tires, so I had a shop align it. Tracks fine and the tires have worn fine, but the steering wheel no longer snaps back after cornering...at least not as it did. I forget which of the alignment functions influences this, but obviously they didn't do something quite right. Maybe when I take it back to them for inspection I'll ask them to revisit this.

Did they make any adjustments to the steering box?

No, but I've puttered with this in the past to tighten it up. Recently replaced the top gasket, which was leaning and took the opportunity to suction out the juice and make sure the worm gears was not being scoured. All looked fine. Can a steering box adjustment impact wheel centeringreturn...assuming it's not adjusted too tightly?

If your steering box is adjusted too tight, it will absolutely affect center return. And it's pretty easy to get it too tight.

If the steering box is just right, or a tad loose, return to center should be fine.

Since you monkeyed with it, I'd loosen it up. See if that helps. It's a good diagnostic measure, if nothing else.

You had an alignment done. Did you look at shims? New ones will be shiny. Old ones, black/gray from living under the hood... Just look for evidence that they checked them out.
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-Matt I ♥ my ♂

"I forget which of the alignment functions influences this, but obviously they didn't do something quite right. Maybe when I take it back to them for inspection I'll ask them to revisit this"
Caster is the component of the alignment that will most effect self centering. But with caster comes steering effort. Maybe they went too far in making the steering effort tolerable. -- Dave