If you dont mind lots of hills, up and down with the trailer than I 81 would work for you. From BNG you have 2 long climbs up heading south on 81 in PA and then the long downhill grade into Clarks Summit/Scranton. Then I 81 is basically easy drive thru the metro Scranton/Wilkes Barre area. Once you pass the exit for PA 29 Nanticoke, You will have a long climb up a mountain then a short descent then few miles ahead you have another climb near Dorrance and then a decent descent down towards I 80 Jct, Then you climb up one more mountain into the coal country plateau near Hazelton. Now if it is raining, this stretch atop the plateau from Hazelton to Pine Grove can be soupy dense fog. After you pass the exit for US 209 for Tremont/Tower city, it is a long descent down the mountain towards Pine Grove. After that I 81 is flat from Lebanon all the way thru PA, MD into WV then Martinsburg.