Allow me to put an addendum on that....
I dropped the pan on the trans, changed the filter, and refilled it once...now, I apologize, it was years ago, but I don't remember it needing 11 quarts...
11 quarts might be the figure for a bone dry transmission....like a "total capacity" number, not the "service change" number. Dropping the pan will not drain every drop. I seem to recall it was more like 6 or 7 quarts.
It was a few years ago though. I could be wrong. As always, keep checking the level as you refill it. This might sound a little goofy, but on a couple of occasions, when I am really in doubt about the amount I drained, I have been known to pour the drain material from the pan into gallon cans to get an idea how much I DRAINED, which then gives me an idea how much to ADD BACK... not the most scientific thing, to be sure, but if I drain 5 quarts, I pretty much know I better not add back 11 quarts..... crude, but effective.
Good luck.