JUST finished putting new from subframe ,all ball joints , poly bushings ,struts, brakes ie rotors and pads, cv joints, tie rods ,new PS hoses and rack and pump as well as sway bar bushings and ends. Also did rear struts and brakes. While changing cv joints tranny drained and added 4.5 quarts but still cant see any after taking for test drive through the dumb *** fill hole. Shifts a lil slippy. Don't want to overfill. I cant understand why they put fill hole under battery then say to check while running at temp.I guess I have to suspend cables and remove battery to check fluid or is their another way

 

There is a fill plug on the side of the transmission. See post 77 in the thread below for the BMW documentation.
https://www.northamericanmotoring.co...-change-4.html

 

The fill hole is the drain hole. There is a tube inside to, that you fill to and then let any extra drain off.
best way to drain it, is to remove the trans pan. Change the filter while you are at it!