I drove part of that route last year (I-40 to US 160). It's pretty open country, hilly in places; mostly through the Navajo reservation. North of Chile the road gets pretty wavy and in bad shape in places; go slow and you won't have a problem. You won't have trouble finding fuel in Chinle or Ganado. If you get to US 160, go west to Kayenta for fuel, food, etc. North from there takes you through Monument Valley (on US 163). You won't find much in the way of fuel except in Monument Valley itself, and sparse fuel until you get to Bluff.
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