I think it is like Kansas transit said, it depends on the state. I don't go to the north east, mostly run the south, and south east states. The only place I have ever had an issue with something hanging off the front or rear, is S.C. and GA. they both looked at the over hang once and even told me they didn't like it but never gave me a ticket, and didn't make me sit there to wait on a permit either.
A good friend of mine has a 48 foot flat, we both loaded the same 55 foot long steel beams in Blythville Ar. one night. We were both headed to Charleston S.C. He got stopped in MO. for the over hang off the back of his flat bed, but they let me go on with the 2 foot over hang on the back of my step deck. I know he called to get permits and they told him he only needed a permit for MO. and S.C. TN. and N.C. both told him that he didn't even need permits until he went over 60 feet.