The Environmental Protection Agency (EPA), under the leadership of Lee Zeldin and aligned with the Trump administration, has issued new guidance regarding Diesel Exhaust Fluid (DEF) software updates. This policy allows manufacturers to update DEF software to prevent severe engine derates and shutdowns, enabling trucks, tractors, and farm equipment to continue operating without immediate shutdowns if DEF runs out. Instead, vehicles will experience staged torque reductions and speed limits, supporting continued operation while maintaining air quality standards. The guidance has been positively received by agricultural and transportation stakeholders, including farmers and diesel engine operators, who emphasize its role in sustaining jobs, lowering fuel prices, and supporting biofuel investments. EPA officials have actively engaged with state and local partners, particularly in Iowa and Missouri, to discuss environmental issues and promote this policy as part of broader efforts under President Trump's "One Big Beautiful Bill." The initiative is also linked to ongoing discussions about clean energy and innovation, as highlighted by visits to events like the Iowa State Fair.