Sandbags in pickup bed, placement?

Over the axle. Why? Leverage but in a centrifical sence.If you have the weight all the way to the back if you round a corner to fast with limited traction the centifical leverage will cause the rear to slide tward the outside of the turn. When I lived in northern Mich I had a big tractor tire tube cut in half and filled both halves with sand and tied off the ends. They would sit on the wheel tubs and not slide off. that way I still had the whole bed to haul stuff.