There's quite a bit to see, even on paved roads, so a high-clearance vehicle isn't needed, just a plus for places like Canyon de Chelly if you have the time and hire a guide. Otherwise you can ride for a day or half day in a "shake & bake" or just shoot from the rim drives, still good pix along there with the best chance for color along with south rim drive.
The Mancos area between Cortez and Durango (s.w. Colorado) has good color in early to mid Oct. depending upon the weather, most of it visible along good paved highways.
The road into the Needles District of Canyonlands may have good cottonwood with color. Same for the Abajo Mountains by Blanding, though I'm not sure of paved roads into the woods there. If the weather is iffy, probably not a good idea to get too far off the beaten path...
The air this time of year can be hazy or clear as a bell, but the color of the redrock country there, evening without changing leaves, is still spectacular. There's just something about autumn light in the 4 Corners, maybe it's a combo of altitude and desert.
Have a great trip!
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