Signal brief

Cummins disclosed revised engine calibrations aligned with EPA guidance to extend the window before DEF inducements and to accelerate final derate speeds. The move targets uptime improvements for fleets and preserves emissions compliance, applying to over 1.5 million engines from 2017–2018 model years. The updates may boost the aftermarket service opportunity and reduce operational downtime for customers.

• Cummins updates engine calibrations per EPA guidance to extend time before DEF inducements.
• Updates increase final derate speeds: 25 mph for trucks, 50 mph for motorcoaches.
• Updates cover over 1.5 million engines; model years 2017 trucks and 2018 motorcoaches.
• DEF remains required; updates aim to reduce downtime while preserving emissions compliance.
• Customers to schedule updates via local Cummins distributors or dealers.