This operation was a little more challenging to do, only because of the location of the transfer case.
80w90 Oil - 1 Qt
Hand pump for gear oil
The transfer case is located at the back of the engine. Picture your radio but only underneath the car and that is where the drain/fill plugs are at.
The easiest way to get at the drain/fill plugs is to jack up the front of the car. Use the socket wrench (just the wrench, no socket is needed) to loosen the fill plug (top plug). It is at an awkward angle, so you need to make sure you can loosen it before you drain it.
Once the fill plug is loose, remove the drain plug (bottom plug). While the oil is draining into your empty container, clean the drain plug and prepare the new oil to be pumped or squirted into the fill plug. When the oil is done draining, reinstall the drain plug.
I have found using a hand pump to squirt the gear oil into the transfer case was the easiest method. Keep adding gear oil until it drips out of the fill plug. Reinstall the fill plug. Remove the jacks from the car and clean up. Done!