My problem was the exact opposite of yours-great when cold, horrible when hot. Found out it was a worn out valve body (I hear they are low-grade aluminum)and shift solenoids. But the trans had been abused, so its getting replaced under warranty (I bought the car used). These transmissions seem to have a mind of their own.To stop mine from banging, all I had to do was shut the engine off and restart. Problem gone, for another 20 minutes. It got aggravating-good luck with yours.
