Happened to me only once... pulling a loaded snowmobile trailer, I made it about 20 miles before I stopped for a soda and checked the hitch. it was unlatched and the chains were still wrapped around the tongue. My son had put the trailer on and told me it was ready to go. Needless to say, he got a lesson on how it is supposed to be put on and I got a mental kick in the a$$ for not checking it before driving off. Luckily no damage and it stayed on the truck.