In the ball diff I would not trust anything apart from the team associated stealth diff lube
here's a link for that:
For the nylon gears I use whit lithium grease.
For my ball bearings I use Fantom bearing oil
Heres a link to that:
For the dog bones and out drives I use a dry lubricant.
I wouldn't use any type of grease of lubes that don't dry completly because it will attract dirt and wear out those parts real quick.
You don't need anything for the spur gear.