Hello 1775,
The Trip Routing program is intended to take you the most direct route from point to point. If the route gives you a warning, that will allow the user the freedom to alter the route to their preference. Keep in mind, if you have selected to avoid highways and/or toll roads, than you may find more warnings.
At the current time, only the Good Sam GPS will allow you to specify an RV Type; i.e. Class A, Travel Trailer, etc. I thank you for bringing this to our attention and will forward this to the team that handles the Trip Routing Planner.
Thank you again for your time,
Mark F
Marcus' Rapid Response Team
goodsamcs@goodsamfamily.com