Is it where the halfs bolt at the differential or is it at the end steering knuckles? Those end knuckles leak fairly often I think and there are many on here that have documented the rebuild...not necessarily on a 2000 but similar small yanmars and I bet there all very similar inside. Search front axle leak or steering knuckle leak or something similar and I bet a few results pop up. Someone is bound to know of one off hand or has a link ready. I don't have time now to search for one though. I know Jake (JDgreen or something like that is his name here) did one on his like 186 or whatever model he use to have. A guy just tore apart his front axle in the last month or two, but I don't think he got to the steering knuckles his issue was in the middle and gears but had the axle torn down. Those are just off my head the ones I can think of but I know there is more.