[cycleguy55]

In and out of the shop on Wednesday, and all is good now. Turns out my assessment was correct, and it seems the UCA cross shaft shifted relative to the spring hat. The front bolt on holding the cross shaft to the top hat must not have been properly tightened during the wheel alignment in July. I don't know whether they put a piece of pipe on the wrench this time, but I tried tightening it further when I got it home and it didn't budge.

BTW, it appears there are serrations are on the bottom of the cross shaft. They're supposed to 'bite' into the mounting surface once the bolt is tightened sufficiently, thereby preventing movement. That's the theory anyway. I guess if the serrations don't hold you replace the cross shaft.