I am in love with these tractors, they have a traction that a normal tire or a rubber track would not even dream of at the same power. I have seen one plowing uphill with four fearful reversible plowshares. But there are two problems, one the purchase cost, two every time you have to move. -How do they work with the bar blocked, it is not known, especially uphill, the best way to ruin the clutches then the tractor leverages a gear because the machine is not free. What does that caterpillar have to do with the old 70's?