Transmission leak

my truck leaks transmission fluid only when it is driven more than usual. i drive back and forth to work and its fine but if i am driving around stuck in traffic or have a passenger it leaks really bad and smokes alot. when i check the fluid its empty then. but if i let it cool down and fill it back up its fine again.

What is the question?

Year, make, model, engine size. When was it last serviced??


Not the OP but the new function gets confusing. It seems like it is a Ford Explorer. Have to wait for OP for the engine.

My daughter’s ford Taurus does very similar - if driven greater than usual distance or on interstate. It can leak catastrophically - otherwise ok. Two mechanics have tried to fix leak. Don’t know why it still leaks sometimes.

BTW - it is a 2003. Has almost 100 k miles

Two mechanics have tried to fix what? In other words, where do they say it is leaking from?