Max. trailable beam
The widest legal beam of any vehicle permitted on the highways is 102 inches, or 8''6". Beyond that point you would, depending on the state you are in, require permits and or escorts.
I''m sure someone will pop up and say that you can do what you want, that the cops aren''t going to bother you, yada, yada, yada. But as one who is familiar with the Title 49 FMCSR''s, and USDOT/FMCSA Regs I know of NO expemptions to private persons allowing them to moved loads of any type exceeding legal dimensions without meeting legally mandated safety requirements and permitting processes.
If you are wider than 102" - Check with the Department of Transportation in your home state....they are the gospel....not the local police. If you are taller than 13''6" when on the trailer....you are in jeopardy of striking a bridge or powerline. At that point you will require specific routing. Statutory heights east of the Mississippi River are 13''6", and west of it they are 14''4".
If your local DOT says its ok to move it without a permit....ok, but make sure you record time, date, name and badge number of the officer who gave you the go ahead.
If you are less than 102"/13''6"....ignore the above, hook up, check your lights and safety chains and travel.