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.

At Cummins, we're never satisfied with the status quo, so virtually every critical component has been modified, upgraded and improved. The 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 an expanded X15 portfolio in 2020, delivering the choice you need.

The X15 Efficiency Series has the best fuel economy of any big-bore engine in the industry, delivering up to 3.5% improved fuel economy from base engine improvements alone. With those changes the Efficiency Series is set to meet Greenhouse Gas (GHG) and 2021 fuel economy regulations a year ahead of schedule, so you can start making bigger profits right away.

In 2020, the X15 Efficiency Series boasts new EX ratings, which deliver expanded powertrain capabilities that can deliver up to an additional 1.5% fuel efficiency increase on top of the improvements gained through base engine hardware and feature enhancements.

The X15 Productivity Series offers unmatched efficiency, value and performance with up to 605 hp and 2050 lb-ft of peak torque, delivering operational efficiency without compromising performance and drivability. The new X15 Productivity Series ratings are designed for multi-purpose, vocational and heavy-haul customers.

The X15 Performance Series continues to dominate the big-bore industry with exceptional transient response and the most powerful engine brake. With up to 565 hp and 2050 lb-ft of peak torque, the Performance Series delivers power and drivability. Proven hardware and continuous improvements have resulted in reliability that provides peace of mind for trucking operations.


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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