have you checked your solenoid pack plug yet?
this is lengthy but i found the reason for code 62 (converter slip) eventually;
https://www.ford-trucks.com/forums/1...code-62-a.html

had i not eventually found the issue,my next step would have been testing to solenoid pack.

see,the issue with assuming its a mechanical failure (converter) is,that if you replace it,which costs hundreds,and it's not the problem,your out $ and still left with a slipping converter.
for me,as you can see,the miles on the truck didn't add up to failing converter,so i was determined to rule that out until proven otherwise.

as to why she was low on fluid though.you'll want to find out.are you running her too hot,that she's puking out the front seal,or is it just a minor trans pan leak.you need to know and fix this of course.