BadAttitude said:
What makes the Ventrac the choice for slopes, low COG?
In part the low COG. In part the articulated frame. In part the oscillating frame. In part the 4 wheel drive. And I think in greater part than any of those is the weight transfer system that moves the implements weight onto the front axle. That sytem is standard on the Model 3000 and the Model 4200, I believe it is optional on the 4100. Steiner also has a similar weight transfer system that shifts the implement weight onto the front axle.
The combined effect of all the features is what makes it work so darn well.
If a regular tractor drives its front right wheel up onto a 4" tall rock then the entire right side of the tractor lifts, the right rear loses some traction and the weight shifts to the left. Most tractors have a front wheel assist as opposed to a true 4 wheel drive so traction is greatly enhanced but still not as good as if all 4 wheels were positively driven. On flat ground that is not a big deal, on a slope that could be tragic.
If a Ventrac drives its front right wheel up onto a 4" tall rock then the frame oscillates, the right rear tire remains firmly on the ground and maintains traction, the front part of the tractor will shift some weight to the left side, but the rear of the tractor does not shift any weight. The implement, due to the weight transfer system, actually moves 70+% of its weight over the front axles to keep increase traction on the front wheels. All 4 wheels are driven equally so traction is constant. On flat ground all this is irrelevant, on a slope it is amazingly stable.