My wife brought a 1984 Celica before we got married. The car was driven about 100,000 miles before I started to take interest in maintenance. I was also told by several mechanics the same thing that Cerbomark was told. The car now has 225,000 miles on it. It has the original filter in it. It does have a slight leak and I just add fluid to it when needed. The car does not have any kind of shift problems. At this point I would not change anything on it. If it does develop a problem than I would try changing the fluid and filter. All the cars that I have owned since . I have changed the fluid/filters on a regular schedule. Two of the cars that I have. One of them had a new tranny installed under warranty (4,000 miles) and one needed a new vacuum module (26,000 miles) installed under warranty. GO FIGURE!