Salt Lake City, UT to Sedona, AZ

Resist, have a look at the area on Google maps. The first exit I'm strongly suggesting that you bypass is only 2 miles south of Flagstaff, but still about 25 miles north of the north end of Sedona. That is Hwy 89A which winds through Oak Creek Canyon. Not easy for a large motorhome. Driving 40 miles down I-17 gets you to Exit #298 (Hwy 179), which is about 6 miles from the south end of Sedona, and an easy two lane road.

If you have a toad, definitely explore Oak Creek Canyon after you arrive in Sedona.