If it is leaking from the top, first check the breather line. You should be able to see it, if not reach it from below and behind the diff.
It comes out at the top, visible in the above pick just to the right of the differential ring gear.
edit: Also make sure it isn't engine oil, leaked from the filter during an oil change...
-Charlie
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'99 4Runner SR5 Auto -
4WD swapped
'89 Camry Alltrac LE 3S-GTE 5spd
'17 Chevy Volt Premier
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