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A few more comments: A "Ford Dealer" is not Ford, and certainly not Ford Engineering. Of course Ford isn't perfect, but we shouldn't transfer distrust for a lousy dealer to Ford. You could change the transmission fluid every 10k miles and it would have no effect on whether your transmission fails (as we are discussing). It has nothing to do with "normal wear" and nothing to do with the bearings. The failure appears to happen as a catastrophic, abrupt event where a ring (I suspect it is friction fit) on the transfer shaft slips which then allows the shaft to shift back and forth allowing gears to hit each other or rub against the housing. In my case the corners of all teeth on one gear were sheared off, groves were worn in the housing (as pictured by Ford) and the end of the shaft eventually wore a hole through the housing. The bearings were still amazingly good. This problem has nothing to do with the prior condition of the fluid. What we feel good about doing is often based on what we've heard and how we interpret it, not engineering data. Personally, anyone can change fluid as they like, but for other folks reading this forum, we shouldn't suggest that deviating from the published schedule is recommended or will provide longer life.

Ask yourself, am I comfortable with changing the fluid at 120k or 150k? Will it help at 120k? Maybe, maybe-not. Will it hurt to go to 150k? Again, maybe, maybe-not. What really counts is what results in you feeling good about your level of upkeep. I changed mine at 100k, despite the manual calling for 150k, 2013 SEL, mostly because it was what I felt good about based on my personal experience from 40+yrs of car upkeep. Trusting your gut may help and in this case is doubtful to hurt. The oil changes a 3k by a lot of folks is a holdover from 30+yrs ago, and a lot of people will not change what works for them. Thanks for the read.