Cummins ISX11.9 receives EPA, CARB certification
Like the lineup of on-highway Heavy-Duty and MidRange engines, the engine utilizes Cummins Aftertreatment System with Selective Catalytic Reduction (SCR) technology.
Cummins Inc. received certification from the Environmental Protection Agency (EPA) and the California Air Resources Board (CARB) for its ISX11.9 diesel engine. The new ISX11.9 is an expansion of the industry-leading Heavy-Duty engine product line for Cummins and will commence with full production in August.
Certification of the ISX11.9 rounds out the complete lineup of Cummins engine offerings for on-highway applications for 2010.
The current EPA regulations took effect Jan. 1, 2010, and are the most stringent in the world for on-highway commercial vehicle engines. Cummins ISX11.9 meets the emissions regulations for Oxides of Nitrogen (NOx) and Particulate Matter (PM) of 0.2 grams and 0.01 grams per brake-horsepower-hour, respectively.
The rugged ISX11.9 builds upon the legacy of strength and performance of the Cummins ISM engine and the proven technology of the ISX15. It features an enhanced cooled Exhaust Gas Recirculation (EGR) system, a single VGT Turbocharger and the proprietary XPI fuel system.
Like the lineup of on-highway Heavy-Duty and MidRange engines, the ISX11.9 will also utilize Cummins Aftertreatment System with Selective Catalytic Reduction (SCR) technology.
Featuring better pulling power, excellent driveability and stronger clutch engagement torque, the ISX11.9 is designed for rigorous duty cycles, including those for work trucks such as dump and mixer trucks, and refuse applications. Additionally, a full suite of horsepower and torque ratings are available for fire and emergency vehicles, recreational vehicles and motorcoaches as well as tanker and day cab operations in Class 8 trucks.
More Motorcoach

Biz Briefs: STV teams with Amtrak, Motorcoach Operators Boost Fleet and Land Contracts, and More
From manufacturers and suppliers to transit agencies and motorcoach operators, these updates offer a snapshot of the projects, partnerships and business moves driving the industry forward.
Read More →
EPA Proposal to Ease Diesel Emissions Compliance Could Improve Reliability for Motorcoach Operators
The EPA is proposing to remove DEF-related engine derates for new heavy-duty diesel vehicles, a change bus operators say would improve safety and reliability while sparking debate over the future of emissions enforcement.
Read More →
Minnesota's Rustad Tours Takes Delivery of New MCI Motorcoach
The latest addition represents Rustad Tours’ 17th new MCI coach, marking more than four decades of partnership between the two companies.
Read More →
Biz Briefs: Endera Delivers to California, Safety Vision Teams with San Antonio's VIA, and More
From manufacturers and suppliers to transit agencies and motorcoach operators, these updates offer a snapshot of the projects, partnerships and business moves driving the industry forward.
Read More →
Modernizing Mobility with CharterUP CEO Armir Harris
From digital transformation to evolving customer demands, CharterUP's Armir Harris offers his perspective on the transportation industry's next chapter.
Read More →
Bipartisan BUSES Act Seeks Changes to New York City's Bus Idling Enforcement Program
Backed by motorcoach operators, the legislation seeks to balance emissions goals with passenger safety by allowing limited idling for inspections, accessibility needs and extreme weather conditions.
Read More →METROspectives: CharterUP CEO Armir Harris on Modernizing Mobility
From digital transformation to evolving customer demands, CharterUP's CEO Armir Harris offers his perspective on the transportation industry's next chapter.
Read More →
Reinventing Fleet Maintenance with Real-time Visibility and AI
Transit leaders need to know what needs fixing, where to look, who is responsible, when work is completed, and what it costs without having to chase information across disconnected systems.
Read More →
ABA's Ferguson Testifies in Support of BUSES Act, National Standards for Bus Operators
The BUSES Act would create a nationwide framework preventing state and local governments from enforcing bus idling restrictions of less than 15 minutes, a threshold consistent with existing Environmental Protection Agency guidance.
Read More →2026 METRO Buyer’s Guide & Directory
Searching for the right vehicles, technology, equipment, or services for your public transit or motorcoach operation? This industry guide brings together manufacturers and suppliers from across the transportation market — all in one place. Download it to connect with the companies that help agencies and operators improve mobility, enhance operations, and move their organizations forward.
Read More →