For my 2004 X3 (E83), I filled it using gravity method and the RIGHT side on the car on ramps.
I did this in 2018, 4 years ago, so far so good.
All info in this DIY below. I bought the ATF from local Menards hardware store.
DIY 2004 X3 (also X5 E53) E83 ATF SIMPLE Drain/Refill using Gravity!
https://xoutpost.com/bmw-sav-forums/...g-gravity.html