I have a 2004 1.8T convertible automatic transmission with 40,000 miles. It running fine and I want to keep it that way. I just wanted to get input from some of you guys who know this car way better than I do. I was considering having the transmission fluid and filter changed and considering using Royal Purple trans fluid. I know the ol' saying, "if it ain't broke, don't fix it" but I really don't want to wait until something does break. Any thoughts/comments on this would be greatly appreciated. I'm not the original owner and as far as I know the transmission has never been serviced. Thanks in advance for any advice.