OK, I'm of limited value here but I used to spec out vehicles for a local fire rescue. We used Fords exclusively and they were great (F350) but somewhere around 1998 (I think) Ford and International got into this big pissing match, the result was that International quit building Diesels for Ford and that Ford started building their own..which IMO were turds, at least for awhile, enough of a turd that we went with another manufacturer.
That's not much, but I hope it helps