I've had good experience getting better fuel mileage in my daily driver with full synthetics, and if its good enough for the car, should be good for the tractor
The web site you listed has Hy-Trans Ultra SSl listed. I think the NH Master Trans is the same. I asked if they were the same a few weeks back and got different answers.
I've had good experience getting better fuel mileage in my daily driver with full synthetics, and if its good enough for the car, should be good for the tractor