Improving snow traction

Snow tires/studs and toss 400 to 500 lbs of sand bags in it over the axle. In my 3/4 4X4 Cummins I have 800 lbs in it and my 77 Aspen beater I have 200 lbs in the trunk. No problems going over mountain passes. Both have aggressive studded tires. You do have to adjust your driving for the conditions. I usually see more 4X4's slid off the road because people think in four wheel drive you can drive like it's dry highway.