Going to be very stupid here; but, if you have a front tank on a folding drill it balances lovely at the ends but weights the tractor down creating massive ruts if you are working on tender ground? I know you shouldn't be on the land if wet but sh!t happens. If you try to be clever and put press wheels under the tank to take some weight surely that creates more problems as its not across the full width of a folding machine? Is the answer simply to make sure the tractor is correctly shod? To be fair all the pics taken by @Phil P and @Bob lincs don't show any issues. All run by hydraulic fans these days? Any thoughts?