OK I see the red silicone in that pic. If it was my tractor I'd just bite the bullet and pull the rear out and open it up and reseal it. New axle seals, tube gaskets, drill the oil return holes, new cork gasket etc. It's not an overwhelming job. I'd also stick a set of Xtreme GT braces on then you'll have a bulletproof tractor that will last for many years of hard use.
