I've got my X1 on jackstands right now doing all of the fluids. The transfer case on my 35i does not appear to have a drain plug, so I've been sucking out the fluid with a handheld mityvac and various diameters of tubing. The fill plug is obstructed and there seems to be no clear path to the bottom of the unit.
So far, I've gotten out exactly 500mL of fluid. It's very hard sticking the tube in to get more fluid out, and I truly don't know if the case is empty or not. Does anyone have the official spec for the X1 35i transfer case capacity?
It seems that older xDrive E90 vehicles had a drain plug, but ours do not.