mrwizard, do you have some trick to suggest as to how exactly you would secure a bag of sand in the back of the truck? I would really like to know how, since I share the same concern as you do, but have not yet figured it out.

 

lol if he goin fast enough in the snow that if he hits somebody or something and 50 lbs comes flyin he was goin way to fast in the first place and needs a good smack in the back of the head

 

Try using plywood from the wheelarch to the tailgate to form a triangular shape along the side of the box, the wheelarch and the corner of the box/tailgate and fill with 150lbs of sand each. Where I live after a few days it freezes solid for all winter and you cannot remove it unless you flip the truck ( this is how my buddy did it) or wait till it thaws in spring.