Best route Raleigh-Nashville?

I am not a trucker but am pulling a 14000 lb trailer with a diesel truck and need your advice on the best route from Raleigh, NC to Nashville, TN.

I know I will have to go through the mountains, but is it better just to go I-40 all the way or is it an easier haul going up 52 out of Winston Salem to 74 north to 77 north to 81 south through Knoxville and back to 40. It looks like it is only about 6 miles more, but what are your thoughts?

Thanks so much for your help.

 

Thank you all so much! I will definitely take 40. Your help is more than appreciated!!!

 

I'm actually pulling a 14000 lb fifth wheel with my '04 f-350 diesel with the 6.0 liter. This is my first big pull with this rig, and I'm just not exactly how sure the truck is going to pull the trailer. This is why I am wanting to know what you all think is the best route for me. I have been both ways before, but with a much lighter trailer and much smaller truck. I do remember the northern route seemed to have an aweful lot of smaller hills to climb between knoxville and the 77 south section. My dodge 1500 worked pretty hard on that section.