How to make a heavy vehicle (it is difficult to move, its wheels slipping at the start).
For wheels, I use
For heavier vehicles set "density" in the physical material.
class MyWheel extends UDKVehicleWheel;
const factor = 500;
const factor2 = 1000;
const WheelRadiusConst = 30;
However, even for very large values of "density" a machine is not becomes slower and rises to almost any slope without slipping.