Do you grease or lubricate the jack legs?

Yeah, if you drilled a hole through the outer housing, and sprayed when the leg was down you could get some lube/spray on the screw, come to think of it. Of course if you did it while the legs were assembled, you'd now have some metal filings down in the screw area, or on the sides of the leg.

I wish I had done this when I had mine apart, but simply didn't think of it. 20/20 hindsight.