Here's some info on expected life. Pretty sure you have the A440F if it's mated to the 3FE. The 80 already has an air flow ATF cooler (the 62 does not), so you are starting out with less potential for overheating the tranny.
https://forum.ih8mud.com/60-series-wagons/184676-official-how-long-does-a440-last-thread.html