Just to be clear, there are two types of free play.
One is "In and Out" play which you check with the wheel off the ground and you push and pull on the tire or axle shaft. This is not super critical unless it gets out of hand which is ultra-rare. There are shims to take care of this but you have to remove the trans-axle from the tractor to deal with it. The procedure is covered in the Transaxle Service Bulletin which will be posted HOPEFULLY soon in the Tech Section by me.
The 2nd type play is the one I was referring to in the other thread and that is "Up/Down/Side to side" play that indicates a worn axle bushing. There is no spec that I'm aware of. In my opinion, if you can detect it by feel, then wear is there. The question then becomes "What shall I do about it?. That depends.
How bad is it? If the seal isn't leaking, then it can't be too bad yet. And if you have no real reason to pull the trans-axle out, then you could put this repair off until you see signs of oil seepage beginning and then schedule it for a winter-time project. If you have to clear snow, then buy a second tractor. :sidelaugh: You know you want one.