I am afraid that there is no right answer to your question. A 33 foot 5th Wheel Trailer will be allowed in the majority of federal, state, private and BLM Camping areas. But because of its size it may be restricted in some of them.
The other factor is that unlike a motorized RV the length of the RV is increased because it is being towed and that may cause some problems on certain access roads to get to primitive camping sites.
Since I do not know what camping areas you want to go to I cannot tell you how restricted you will be a with a 33' Fifth Wheel Trailer.
You are going to have to do a little bit of research to determine if this 5th Wheel is going to work for you and where you want to camp. Your first stop should be Recreation.gov where you can get information on camping on public lands such as national parks, national forests, BLM lands and army corps of engineer projects. In most cases the information will include RV length restrictions. For information on camping in state parks you should visit Stateparks.com.
For even more information on Camping in State, Federal and Private Campgrounds you should purchase a copy of the most recent Good Sam RV Travel Guide & Campground Directory which provides a wealth of campground information including length and height restrictions.
I hope that this information has been helpful to you.
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