I have a 03 Taurus which runs normal, when running the tranny fluid is normal and runs fine when you shut the engine off the transmission fluid drains out through the top of the dipstick tube. It doesn't have 50,000 miles on the car yet but is out of warranty. could this be the torque converter leaking off fluid

Fluid expands when it gets hot. Either it is over full or the trans is overheating and may have problems.