I have small leak from drain plug on differential side, plug B per schematic. I figure leak was about 3/4 sq ft on floor (couple oz?) wondering if I can put a little torque on it, or will that risk breaking it, it feels snug. Is there anyway to add oil? Still moves, do I risk damage mowing with it, or is it something that needs fixing immediately or risk $100's in damage? Any help greatly appreciated.