hi,
  i have a 2002 ford explorer xls auto v6 which i brought used at 52k
miles and after driving it for 8k took it for transmission
service,radiator flush,power steering flush and replaced fuel filter at
a ford dealer.
after the service i notice fluid leak on the floor on a regular basis
and took it to the dealer who said power steering hose was leaking and
he replaced it.
then while driving on the highway it started smoking which i did not
realise but i driver from behind informed me so i stopped and on
opening the hood it was letting out little smoke and some drops of
trans fluid was falling on the road but nothing major leak.
so i had it towed to the dealer and he said the torque converter seal
had gone bad and needed replacing even though the vehicle was driving
perfectly fine.
i noticed that on driving short distances there were no fluid drops on
the garage floor but if more than an hour and then i parked there would
be a few drops but no puddle.
so i took it aamco and they cleaned the whole underbelly and i drove
around for 2hrs then i took it back to them and the leak was from the
top of the transmission and nothing major.

they said the dealer had probably over filled the transmission fluid
during service and that was leaking through the breather once the
transmission got hot and would stop eventually once extra fluid got
out.
2002 had no trans dip stick.

is that a viable cause or there something else.
he also opened the seal of the transmission and it was dry inside and
the vehicle drives totally fine.