I dont understand the environmental benefit of DPF. Diesel particulate is solid carbon particles that are too big to stay suspended in the air for very long. Thats why you can see them. They quickly drop to the ground and effectively capture the carbon from the fuel in a form that will not contribute to CO2 warming...ever. I guess that in a highly urban area, soot can be a problem contributing to filthy streets, but tractors are rarely used in cites. I guess its like the fable that electric cars are more environmental, just dont look into the mining that is required for the batteries.