There is Black Mountain in NC that going west is a pretty good pull for 4 or 5 miles then levels off. At the western edge of NC is a curvy, twisty section of I 40 called the Gorge. Semi's must stay in the right lane, it's not to bad but you must stay on your toes as there has been many wrecks just look at the road and concrete middle barriers for all the gouges from wrecks at every curve in the road. I75 N in TN is hilly with one long pull up hill but nothing to worry about. If you're going I 40 to I 75 I would recommend I 40W "I 640 W" to I 75N
