3Racing Oil Gear Diff
Here in Australia, we use from 300 000 to 500 000 weight oil in these diffs. The oil is like treacle, but it sure gives great acceleration out of the corners and no diffing out action.
The thicker the oil the more wear on the drive train. The 500 000 will mean you need to check the blades regularly otherwise you will damage the alloy outdrives.
Later,
50 Cal.