The truck is definitely not balanced. Weight in the rear, directly over the axle will help. I use at least 200lb of weight to be effective though.
Last winter I didn?t bother putting any weight in my Dakota because I use it so much for hauling crap, and it did ok as long as the snow was not too wet. I?m probably going to put weight in it this year, but I?m thinking of bolting a heavy steel plate down to the bed instead so I don?t take up any space in the bed.