we use to have the same probs with real tanks in the snow. out in germany in the 80s we had some chieftan tanks and the tracks would fail in deep snow problem being snow compacts then increases in size causing tight running gear.even if it didnt happen the tanks were no good in snow anyway because we had no traction and the tanks would slide of the road sideways, cross country was the best but a blowlamp was always in use to melt the ice of the idlers