As Hayseed said they could play with the weighbridge, there was a movie made about it i cant find it on youtube, they would come on a weighbridge where you weighed the truck then the trailer. They would let the air out so it threw weight on the truck, thyen as they pulled forward put plenty air in so the pusher was taking weight of the truck and make the tri heavy,the movie was based on the grain board in nsw i thnk it was based on true events i think in the movie it said they discovered not as much grain in the silos as there should have been
