Here is what we did. South out of Pawtucket, RI on I95, thru Connecticut to I287 West over Tappen Bridge on New York State Thruway(toll). On to I78 West to I81 South to I40 West in Tennessee. We kept on I40 to California. You will have to head south before or in Tennessee get to NC, presumably I26 or I40 to get to Asheville. We drove a 25 foot Thor Sprinter Siesta, no toad. Roads mostly 2 lanes each way, lots of semi trucks. We used Good Sam trip planner to plot route, you can check RV parks and Flying J/Pilot truck stops as needed. Avoided congestion and restrictions on roads and tunnels for RVs and propane in NY and NJ. Don't know if it is the best but worked great for us. Was approx $40-45 for tolls versus $15-20 for extra fuel. You can use states toll calculator to figure toll costs, PITA (pain in the axx).