From what Scotty Kilmer , who is a 50 year experienced auto mechanic states on his YT channel, a very high mileage automatic transaxle/transmission fluid change, on a vehicle that never had a trans fluid change , can actually be detrimental to the unit. I've heard the same from a few reputable sources. It seems that there is so much grit from the wear parts in the trans , that it's what actually keeps the trans from slipping, that grit circulating through the trans fluid? So , I don't know, if the T axle fluid was never changed, if it would be a good idea, to change it , at that many miles? I too, have heard to the contrary.
I had a V6 Fiero Formula I bought used at ~50K & got an auto transaxle power flush & fill of the fluid , for the first time @ 60K miles, then put a plug on the transaxle oil pan , & changed the fluid in the pan , just about yearly , @ around 12,000 mile intervals, & put on a Magnefine auxiliary inline trans filter & NEVER had a transaxle problem , & when I sold it at 165+K miles , the transaxle was still working flawlessly. Those 125C transaxles were said to be weak , but with the those things I did to it, & the addition of putting a small auxiliary trans cooler on it too, along with the rest of the maintenance I did, seemed to help a lot to avoid costly repairs . & that's on a unit that was said to be not a very stout one.
Even tough the transaxle on the Taurus which is a "joint venture" designed T axle that GM co
produced with Ford , is said to be pretty good, I'm going to continue my frequent fluid changes, & I'm going to put a "Magnefine" filter on it & I'm trying to get the info on how best to install an auxiliary cooler on it.
So I think the Ford dealer may be right on not recommending a fluid change in your case? How many miles do you have on it? If it's over say 75-80 grand, maybe not?