trucking

Daimler Updates 330,000 Trucks Following EPA Emissions Guidance Shift

Daimler Truck North America is deploying engine software updates to approximately 330,000 vehicles in response to revised Environmental Protection Agency guidance on diesel exhaust fluid systems. The rollout covers Detroit DD13 and DD15 engines across 2021-2025 model year trucks and will conclude by year-end 2026. New Freightliner and Western Star units already carry the updated software. The EPA scaled back certain DEF-related restrictions in August and clarified in March that manufacturers may implement software-based alternatives to traditional emissions controls. The revision raises speed-limp thresholds from 5 mph to 25 mph when maintenance issues occur, granting operators extended repair windows before full performance inducement takes effect. Daimler has briefed its dealer network to ensure consistent customer support throughout the update cycle.