That's a pretty big loop you are planning, so don't try to fit more in the "shoebox" than will fit.
🙂from denver to moab on 70 and 191 is good, but there is a scenic byway you can get at exit 212 off I 70 that will take you along the CO river into Moab.
From Moab down to 163 down to 160 and west to 89 then into Grand Canyon via 64..all passable roads, two lane. this is not a crowded area of the US, so there will be miles and miles of vacant land between a few small towns, but all the towns will have fuel. Kayenta, AZ, in the middle of american indian country, has a good sized grocery store if you need to get anything before going on to Grand Canyon.
From GC, on west to Las Vegas. 93 from Kingman up to Vegas is good and will cross the CO river on a very high bridge, but they require the trucks and rvs to use the inside lane. plenty of room.
Do skip Death Valley and Mono Lake at this time of year. It's just not worth the discomfort, and the grades going down and climbing out of DV are really pretty tough. Barstow to Bakersfield and north is good, and if your time is good, take 198 west and north out of Visalia and drive up through Sequoia Nat'l Park before going on to Yosemite. Sequoia has the big trees and it's a very scenic drive, etc.
Crossing NV and UT on I 80 is pretty boring...all high desert country but it follows, roughly, the way of the first intercontinental railway. And in UT you will pass by the Salt Flats where they test high speed cars and motorcycles... like in the movie "The World's Fastest Indian" with Anthony Hopkins. I think there is a viewing station along the highway you can stop for a break and maybe see something of the testing area.
Have fun.
TexasShadow
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