What kind of lubricant is used inside the rear differential? I'm not sure yet but it looks like I may have a leak. I'm also hearing a whine in the transmission, at what mileage should the transmission fluid be drained and replaced? I'm getting close to 100k and I want to get everything that should be replaced, replaced, drained and filled with new lubricant.
Thanks for all the help

 

I'm under the impression that the drivetrain is mostly "filled-for-life", which is of course a blatant lie. I had my gearbox oil and transfer case oil changed at 42k miles and the rear differential oil changed at 46k miles.

This is what they (Jag-specialized independent shop ran by a fairly well-known guru) put in:
Gearbox (manual!): Castrol Syntrax 75w-90
Transfer case (center differential): Castrol Syntrax limited slip 75w-140
Rear differential: Differential 75w-140 SAF-XJ
Each time they also added a dab of X1R, which is some sort of a lubricant additive.