This is all great information. We are pretty careful types, so we'll check all the usual stuff. My husband grew up in that area, so he knows the effects of the AZ weather on vehicles. We'll try to balance reasonable preparation with play it as you go in terms of supplies. We aren't delicate or divas, and can do without! We're mainly looking forward to the journey.
Any tips about actual travel? Etiquette we may not know about? I saw a trip planner on the KOA website that laid out their sites all along the way so we could sort of plan where we might stop - are KOA's ok? I've never used one before.