Related: Cummins Invests Big in Truck Electrification Technologies
Cummins Shows Medium-Duty Lineup, EPA/CARB Natural Gas Certifications
The Cummins Westport B6.7N natural gas engine recently received certifications from both the U.S. Environmental Protection Agency and the California Air Resources Board.

With the recent CARB and EPA certifications of the B6.7, all Cummins Westport natural gas engines now have near-zero certifications.
Photo: Jim Park
Cummins anounced at The Work Truck Show in Indianapolis that its commitment to deliver sustainable products and lower NOx emissions continues with certification of the Cummins Westport B6.7N natural gas engine. It recently received certifications from both the U.S. Environmental Protection Agency and the California Air Resources Board. The B6.7N meets the optional Low NOx standard of 0.02 g/bhp-hr, a 90% reduction from engines operating at the current EPA NOx limit of 0.2 g/bhp-hr.
"All three platforms of our natural gas product line are now 'near-zero' certified," said Tom Hodek, director sales and marketing and new product development, Cummins Westport. "We certified the ISL G back in 2016 to 0.02. In 2018, we certified the ISX12N to 0.02, and the last piece of the puzzle, the 6.7N, is now at 0.02 also.
"On top of that, we are also 2027 GHG compliant. From an emissions perspective, you are not going to find a cleaner engine on the market today."
Next-Generation Medium-Duty Engines
Cummins introduced its next generation of medium-duty on-highway diesel and natural gas engines on Tuesday at the Work Truck Show in Indianapolis, as well as enhancements to the 2021 B6.7 and L9 diesel engines. "We focused on making the engines even more reliable, and more efficient," said Rob Neitzke, Cummins’ executive director for North American truck OEM business.
Enhancements to the next generation of B6.7 and L9 engines were made with customers’ total cost of ownership in mind, Cummins said. Both engines feature extended oil drain and fuel filter replacement intervals, and a redesigned breather that is now maintenance-free.
"Oil drain intervals on the B6.7 can get you up to 30,000 miles or 1,000 hours," Neitzke said. "On the L9, you can get up to 50,000 miles or 1,500 hours. Fuel filter intervals on the L9 are up to three times linger than the current product while the B6.7 interval is up to four times linger than the current product.We are also excited about the improved connectivity of the products coming into 2021," he added.
Cummins’ suite of Connected Solutions is built on an open digital platform that is interconnectable with diverse environments. The portfolio offers fleet management tools and cost-saving technologies that include a suite of remote-monitoring, reporting, calibrating and servicing solutions designed to enhance the customer experience across product lifecycles. In the future, prognostics will help detect and diagnose issues early and be paired with preemptive parts procurement to streamline service experiences.
"The L9, coming into 2021 still has the best power density in the industry, but we have also reduced frictional losses in the engine, further optimized combustion and now we are able to deliver fuel efficiency improvements up to 5% across the board," said Neitzke.
For truck applications, the 2021 L9 base warranty is now three years / unlimited miles.
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