A904 Cooler Line

Some times, replacing the fluid will cause problems. That is caused by the new fluid having fresh additives, that are not depleted, and that cleans the trans. If your trans is in that bad condition, it should be gone through, anyway. While having the pan down for the filter replacement, I would suggest adjusting the bands. What kind of problems are you having with the trans?
I have owned the car for a little more than a year, and it has 72,000 miles on it. The only problem I have had is this: After idling at a long stoplight while in drive, started into intersection, trans lost all ability to transmit power, engine just revved. Pushbutton selector, tried all other gears, no result. Pushed car to parking lot. Checked trans fluid (in neutral with engine running) and it was at the correct level. Sat a while to think (5-10 minutes). Tried it again, and it worked fine. Drove home about several miles with no problems. Otherwise, I have not noticed any other problems, no shift issues that I noticed, no slipping that I noticed.