I put a post up last week about an oil change shop putting the incorrect transmission fluid in my Sebring. With the SPIII universal fluid they put into it, the gear changes were abrupt and the car engaged into gear very hard. Now that the correct ATF+4 fluid is back in place, the shift quality and gear engagement has been constantly improving and now the transmission is shifting extremely smooth and gear selection is quick with no jerking. Would an Automatic transmission self heal itself? The car went from feeling like the transmission was on its last leg to feeling like a brand new car.