Completed both differential oil changes today, again fill and drain plug on front and only drain plug on rear. The rear took a little over a 1L of fluid and the front a little over a half a liter. Front diff oil was darker and stronger smell, the rear was basically new. I have an X3 2014 35i with 95K. I did want to ask if the wetness I noted on the oil pan? near the front axles is of concern, see photos at link, too big to upload using my phone. This was on the right side.
https://photos.app.goo.gl/w5A3sdYuu9YvPqX58