Utah national parks trip in June

There's nothing bad about Hwy 12 for big rigs. The road is not narrow. It's a standard highway width. You can easily make the turns. If you look at aerial views of it you'll see that it's not a straight down dropoff in that small area. It has a gradual contour. A dropoff would be Hwy 550 in Colorado. We've done that one, too - multiple times. Don't avoid Hwy 12. It's an absolutely gorgeous drive. Stop for a night or two in Escalante and take your vehicle to do more exploring. That area is fascinating. Hike some of the slot canyons. Ask at the Visitor Center.

https://www.youtube.com/watch?v=-S3siTrjUJk

https://www.youtube.com/watch?v=UXTjiXA8M5Q