I don't own that model, but those are some big mountain passes and about what I would expect from that drivetrain with a TOAD. Not only the inclines, but elevation are affecting your engine performance as you likely know. It's one reason many that frequent the west buy "oversized" in terms of powertrain.
That engine doesn't mind spinning at 4000 RPMs, it near where it produces peak HP. Just get used to the added noise and take it easy. The component to be concerned about IMHO is the transmission. Often times tranny temp's can spike on long ascents not only to the the added stress of the climb, but also the lowered coach speed and thus less efficient heat transfer at the radiator. Perhaps others have an opinion with that drivetrain, but consider investing in a real transmission temp gauge if you dont already have one. The stock one in many Ford's is more of a dummy light with an arm in my opinion.
Sounds like a fun trip BTW.
American Revolution 40L CAT C9
Samsung 197, TireMinder, Ready Brute Elite with Wrangler