We drove to and all over AK in 2000, a dream of 60 years finally came true. We had been RVing for one year and never heard of RV.NET. Didn't know or think about tires, especially the 5 year rule or china bombs. Our first flat was in the middle of nothing on a beautiful road and actually it was a thrown tread that smashed the water pump. We had two more treads separate and one puncher on the original 1998 tires.
Enough back story, the roads are for the most part very nice but typical near and extremely wilderness areas and graded roads. The entire 12,500 miles that summer was an unbelievable trip but never again if I have any question about the quality of my rigs tires.
The most unforgettable trip you will ever take and really good tires are the first step. Take two spares if you feel better but probably not necessary. Folks up there are used to having flats, especially on the Dempster but live there anyway. Help is not always quick in coming but it always comes.
Don't forget to keep a journal and download and save your pictures often.