The 70 series have the electronic govoner on the injection. With the 8970 there is a lot less smoke than the 8960. Seen very few engine problems with the JD motors, 8760 up to 8870. Be sure to get the right tires and weight package for what you want to pull. Too many machines of all colors are sold with not enough weight for the HP, makes them cheaper to buy. Should have about 105 lb. per HP. to get the most out of a machine. Heard many bad stories about buing a big tractor that doesn't pull. P.S. Get the most speeds of transmtion you can afford.