how much tranny fluid for a 727

When I drained my 727, I also drained the torque converter. I had to add 8.5 quarts to bring it up to full. I also have heard others say about 10-12qts. I would go buy 10 quarts, add 7 quarts, start it up in neutral to let the converter fill (if you drained it like I did, 1970 and up have drains in case you did not know).. pull the car onto a level surface and check/add as required. If you bought one to many quarts of fluid, you can always return it or keep on the shelf. :) Good luck!