Well, it won't be exactly flat but your DP should be capable. You are in the TN/NC/GA mountains. The roads are pretty good if you stay to the main routes and don't try to take a short cut.
Past Newport TN you will be entering the Pigeon River Gorge. Its a beautiful drive but it has curves and gradual grades. Pull into the truck lane and stay there and go with the flow. There is one tunnel with plenty of clearance and good lighting. Make sure you go to exit 27. The earlier exit for Waynesville will just put you in traffic and slow you down going around town. Mind you, Waynesville is a nice town for a stop if you need a break, plus there are a couple nice campgrounds for an overnight at exit 20, RT276.
You want exit 81 off the Smoky Mountain Expressway at Dillsboro, then you will be on 23.