I’ve got an 03 F150 FX4 with automatic transmission and about 185,000 miles. No problems so far with the transmission but feel like I need to change the fluid along with filter and new gasket. I have been told a total flush is better. I have also been told that a complete flush in an older tranny could cause issues??? What do you think? I know this truck had to previous flushes at about 75,000 and again at around 125,000? Thoughts?