I just got home from a trip to morehead NC in our sprinter based LTV ,ours has the 5cyc diesel bought new in 2007 I think the last of the 5cyc engines , from ohio to NC up down the hills it preformed great going 65plus mph and handling the hills great , round trip fuel avg was 19.8 in a 1600mile run . going up down the hills was no problem , I was passing other cars,trucks, ours a 2007 leisure travel van,mod freedom serenity II 25ft long on a sprinter chassis 3500 series. A B or a C who knows, I like the idea big med or small.