On my 2005 x5 4.4, Ive got that newer style trans pan with the one hole to both drain and fill the pan. The dealer says 'only they can fill transmission fluid with a special pump, while the car is running' and that its impossible to do it on your own.

Ive got a tranny leak on that gasket that I need to fix. Is this really something only the dealer can do? Ive got the parts on order, but I dont wanna drop the pan only to find that I cant fill it later...anyone else do a DIY on this one and have any advice?