How do you check and add gear oil to the transfer case on the left side of the motor?

 

There is a grey cover around the gearcase that you have to take off to gain access to the fill/drain. This is kinda poor design because the fill is 10mm plug on the side near the bottom so you cant really check it and you cant fill it without is being practicly on its side. You can drain it this way also but make sure no matter what thet the fluid is warm or it will take a long time to drain. Not sure what your manual says about how much to add. I know it is not much though. Maybe 1/8 quart. It just needs enough to lubricate the gears. I would also use a synthetic gear oil and synthetic oil for the motor. Did you change the motor oil yet? You should have.