Pulling a 35' camper has its issues, not the least of which is getting into locations you wish never happened. I cannot imagine anyone towing a long trailer of any kind and not having this book. NOTE: It does help if your copilot understands the book and looks ahead otherwise you are better off pulling over to plan where you need fuel (diesel for me) food, or anything else. A real bargain if it only keeps you out of one nasty situation. I have owned three different years, make gifts of the old ones to people who never heard of them, bet they buy the latest edition shortly after!