If you are worried about roads not appropriate for a big rig get an Truck and RV GPS. There are several makes out there. With these you can put in you weight, length, and height and it will offer routs that keep you out of trouble.
There are also two apps that are very useful; AllStays Truck and Travel, and AllStays Camp and RV. Both will show things like low clearance.
Paul, Kathy, and Tux a 4 month Mini Schnauzer
2014 Tiffin Phaeton 42 LH, 2013 Honda CRV
"When the time comes to look back, make sure you'll like what you see"