OTC makes a big adjustable hook spanner, I recently bought one off eBay for $100. I don't know if that will stop the leak. It could be final drive bellows seals.
I have one. I would sell for $75.00 plus cost of shipping from Kansas City,Mo by UPS
However, you can tighten FD bearings with a good strong pry bar. make sure the clamp bolt is loose and the lock removed.
!!! Standing out from Final Drive, looking towards the FD, turn the adjusting nut counter clockwise, that will force the bearing and holder in to force outer and inner bearings together to make a tight bearing fit.
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