The Trump administration has issued new guidance for manufacturers of vehicles and equipment that require Diesel Exhaust Fluid (DEF), aiming to reduce the burden on farmers and truckers. The Environmental Protection Agency (EPA) is providing relief by reducing derating – a feature that forces engines to operate at lower capacity when sensors detect DEF levels – and increasing the time operators have to secure fuel before refueling.
Under the new guidance, farmers and truckers will face fewer disruptions, resulting in reduced downtime and costs. The changes are expected to save family farmers an estimated $727 million annually. This move is seen as a significant step forward in addressing the issues faced by equipment operators, who previously had to deal with rapid engine slowdowns due to faulty sensors.
The new guidance will allow trucks to operate normally for up to 4,200 miles or two work weeks after a fault is detected, and farmers’ non-road equipment will see no impact for the first 36 hours before experiencing slight torque reductions. These changes aim to maintain environmental benefits while restoring control for farmers and truckers.
The EPA’s move is seen as a victory for American industries, particularly agriculture, which relies heavily on DEF technology. The administration’s efforts are expected to improve productivity and reduce unnecessary downtime, ultimately benefiting the food supply and economy.
Source: https://eu.desmoinesregister.com/story/opinion/columnists/2025/08/12/epa-def-scr-diesel-exhaust-fluid-guidance-iowa-farmers/85620917007