
For family farmers battling razor-thin profit margins, rising input costs and stubbornly low commodity prices, even modest reductions in equipment and transportation expenses can make a meaningful difference. A new proposal from the U.S. Environmental Protection Agency (EPA) aims to deliver just that by easing diesel emissions compliance requirements that the agency says have become costly and burdensome for truckers, farmers and equipment operators.
EPA Administrator Lee Zeldin on Thursday unveiled a proposed rule that would revise portions of the Biden administration’s 2023 heavy-duty diesel emissions regulations. According to EPA, the changes could save truck owners an estimated $12 billion nationwide, including up to $6,000 on the purchase price of a new heavy-duty truck, while preserving the vast majority of planned reductions in nitrogen oxide (NOx) emissions.
One of the proposal’s most significant provisions for agriculture would eliminate so-called “engine deratements” on newly manufactured diesel-powered trucks and off-road equipment, including agricultural machinery.
Modern diesel engines equipped with Diesel Exhaust Fluid (DEF) systems are designed to automatically reduce engine power—or in some cases limit vehicle speed—when the emissions system detects a malfunction. Farmers and truck operators have long argued that these deratements are frequently triggered by faulty sensors or software rather than actual emissions problems, leaving equipment operating at reduced power or temporarily unusable during critical planting and harvest windows.
Under EPA’s proposal, new diesel-powered equipment would no longer automatically slow down or shut down because of DEF-related faults. Instead, operators would receive warning lights or audible alerts allowing them to continue operating until repairs can be made safely.
For many farm operations, particularly family-owned businesses with limited equipment fleets, eliminating unexpected shutdowns could reduce costly downtime during narrow fieldwork windows when every hour counts.
Agriculture Secretary Brooke Rollins said the proposal addresses an issue farmers have raised for years.
“Administrator Zeldin is continuing to deliver for our nation’s farmers, ranchers and truckers on an issue that has shown the true cost of government overreach,” Rollins said in a statement. “This proposal to eliminate engine deratements and reform the Biden-era DEF requirements will lower costs, increase safety and keep our nation’s food supply moving.”
Beyond improving equipment reliability, EPA also proposes scaling back emissions warranty requirements that the agency says represent one of the largest compliance costs for truck manufacturers. EPA estimates the revisions would retain nearly 90% of the nitrogen oxide reductions required under the current rule while lowering costs for manufacturers and equipment buyers.
The agency is also proposing additional time for manufacturers to meet certain regulatory durability requirements, saying the extra lead time would allow companies to fully test new emissions technologies before bringing them to market.
Truck and engine manufacturers have argued that portions of the 2023 emissions rule were difficult to achieve within the existing timeline and risked disrupting production. EPA’s proposal would temporarily allow certain engines that do not yet meet the new standards to remain on the market through a system of nonconformance penalties while manufacturers complete compliance.
Although much of the proposal centers on the trucking industry, farm operators could see indirect benefits beyond equipment reliability.
Lower freight costs can reduce transportation expenses throughout the agricultural supply chain, potentially lowering the cost of fertilizer, crop protection products, seed, machinery parts and other farm inputs delivered by truck. Livestock producers, grain handlers and food processors could also benefit from lower trucking costs, helping reduce marketing and distribution expenses.
For grain producers facing depressed corn and soybean prices, any reduction in operating costs may provide welcome financial relief. Many farmers have spent the past two years navigating narrow or negative profit margins as commodity prices weakened while expenses for machinery, labor, land and crop inputs remained historically high.
EPA has also taken several related actions over the past year, including reaffirming farmers’ right to repair emissions-related equipment, issuing guidance encouraging manufacturers to reduce false DEF failure warnings, and requesting performance data from major DEF system manufacturers.
The proposed rule would apply to newly manufactured highway trucks and new off-road diesel equipment, including agricultural machinery. EPA is also seeking public comment on whether similar flexibility should eventually be extended to existing vehicles and equipment already in service.
The proposal will be subject to a 45-day public comment period before EPA considers issuing a final rule.







