[dmarty]

All concrete will shrink (and crack) when it cures. Most contractors will put in control joints every 12 ft or so in a slab. That way it will control where the cracks will be. In your case not under the lift posts. They usually saw-cut the slab about ½ inch deep for the control joints or imbed a plastic strip in the concrete when they pour it. Too late now, though. I wouldn’t worry too much about it, but would try to move the lift posts as far away from the crack as you can. Also try to find a lift that has as large a foot on the post as possible. If you’re really worried about it, you could cut out the area where your posts will go and pour a nice big footing, but I wouldn’t mess with it. You might check with the manufacturer of the hoist and see what they recommend.