 As a farmer, I have thousands of more mouths to feed than the average person. What fuels me to get the job done? The smell of the soil and the hum of the combine. What fuels my equipment? Cenex Ruby Fieldmaster. A premium diesel fuel for the most challenging conditions. Better than any formula yet. Delivering maximum uptime every time. Cenex Ruby Fieldmaster. Fueled by innovation. Powered to perform. Farmers Union Oil Cenex. They prefer Falls and Goodridge.