A couple of years ago when my dad bought a used 2017 f150 it had 44,000 miles now it has 88,000 he has never changed the transmission fluid and I told him next time when he gets a oil change he should get the fluid change but he wants to ask the dealer and see what they say but I already know what they are going to tell him he said he doesn’t know anyone who changes there fluid so how often should he change the fluid? Even tho it is under warranty I don’t want his transmission going out early because of not changing the fluid.
Changing the fluid every 50 to 60 thousand. Don't believe it is lifetime and make sure never to flush the transmission.
I would personally change the transmission fluid on those every 40,000-50,000 miles and sleep easier at night. 88,000 miles (assuming also previous owner did not change the ATF) is relatively long without changing the transmission fluid especially if you tow with it, haul heavy loads, and/or lots of stop and go.
you should check out the ATF topic in our FAQ
