1981 240D auto transmission fluid change question

[wilburtual]

how much fluid is supposed to drain out of an 81 240D auto-transmission when I drop the pan and filter?

here's my story.. transmission started to flare when shifting, figured maybe low fluid level, so i check the dip stick, and its actually showing ABOVE the line when up to operating temp...? i know i've had to top off the fluid in the past every once and a while, so i can't see how there would all of the sudden be too much in there...? and it really feels like theres not enough when shifting.. so i go against the dipstick and add 1/2 qrt - and it helps, shifting is noticeably better. then a couple months later, same things starts to happen, gear shift slipping and dip stick still shows about an inch OVER the max line..

so i figure its well due for a fluid and filter change so i try it out (my first time changing this) I drop the pan and filter, let it drip til it stops, and put a new filter and gasket on. i did not drain the torque converter. only about 2 quarts drained out... is that way too little? i feel like i've read around here it should be more like 4? i check the dipstick after drained and no mark on it (duh) but then I add 1.5 quarts back in and check the dipstick- it shows ABOVE full again??

Am i missing something here...??? i feel like there isnt nearly enough fluid in there to be showing above the full line.. i don't want to under-fill and then drive on it... can the dipstick be messed up and showing the wrong level? it even shows too much when the engine is cold and on level surface....

thanks in advance for the help