Heavy-Duty Truck

Cummins wrote the book on high-performance diesel engines. The ISX15 began as a radically innovative platform – rapidly outpacing the competition and becoming the industry’s dominant big-bore engine over the past three decades.

But at Cummins, we’re never satisfied with the status quo. So virtually every critical component has been modified, upgraded and improved. The 2017 X15 engine series delivers the best performance and dependability in the industry as well as superior fuel economy over competitive engines. So you can blow past other trucks – as well as diesel stops.


Cummins is reinventing the heavy-duty engine category with two unique X15 engines. The X15 Efficiency Series has the highest compression ratio in the industry, for unmatched fuel efficiency and responsiveness, delivering up to 1850 lb-ft (2508 N•m) of torque starting at 1000 rpm.

The X15 Performance Series delivers unprecedented power, with up to 605 hp (451 kW) and 2050 lb-ft (2779 N•m) peak torque. Plus, every X15 engine comes with over-the-air calibration capability, a Single Module aftertreatment system, the most powerful engine brake in the industry and extended service intervals, for maximum uptime.


The Cummins X12 redefines the entire medium-bore engine category (10L-13L), setting new standards for productivity in regional-haul, vocational and intermodal truck applications. Smaller in size – up to 600 lbs lighter than other engines in its class and at least 150 pounds lighter than the next-closest competitive engine – the X12 still delivers powerful performance from 350 hp to 475 hp (260 to 354 kW) and 1250 to 1700 lb-ft (1694 to 2304 N•m) of peak torque. The X12 has the highest power-to-weight ratio of any heavy-duty engine from 10 liters to 16 liters in size.


At Cummins, dependability goes way beyond engine performance. It means being able to count on us to do what we say we will do. Dependability means that you don’t have to worry. That’s why no one comes close to Cummins service and support. Cummins offers the best warranty and extended coverage plans in the industry, and backs them with the largest, most capable support network in North America.

Call Cummins Care at 1-800-CUMMINS™ (1-800-286-6467) for expert assistance from a Cummins Care representative. If you need service, representatives are available 24/7/365 to help locate the nearest available and authorized facility.

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