The new Cummins X15 is the most efficient engine in its class ever created. Using the biggest, toughest parts in the industry, the X15 is ready for any job and can still keep costs low for fleets. The new 2017 Freightliner Cascadia makes use of this powerhouse, and it delivers.

It began as a innovative platform, complete with dual overhead cams, exceptionally strong engine braking and an even tougher head and block, for unrivaled dependability. Customers took notice, quickly making the Cummins ISX15 the best-selling engine in its category, by far.

Cummins X15 efficient diesel engineThe X15 is optimized to deliver more power than alternative after-treatment systems, with 400 hp to 500 hp and 1450-1850 lb-ft of peak torque. But what’s really impressive is what happens when you crest the hill and take your foot off the accelerator. That’s when the most powerful engine brake in the industry kicks in, and you just ease on down the road. You get over 400 braking horsepower (bhp) at just 1300 rpm.

When the X15 pulls on the reins, you can go light on the brake pedal, saving wear and tear on your service brakes while staying in total control.

The X15’s Innovative, Efficient Parts Technology

Virtually every critical component has been scrutinized, modified, upgraded and improved. All that makes the 2017 X15 a completely reinvented platform that delivers the best performance and dependability in the industry. Dynamic electronic features, the high-efficiency VGT® Turbo and an optimized combustion formula have resulted in a significant increase in fuel efficiency and throttle response.

The integrated Single Module after-treatment system dramatically increases cleaning intervals while saving weight and space. We’ve combined the best available components with our advanced engine controls into one fully integrated powertrain package that is so efficient that it is redefining the heavy-duty trucking industry.

Taking advantage of the big-bore architecture, the X15 manages the combustion cycle to achieve the highest compression ratio in the industry, and improve thermal efficiency. The X15 is able to leverage the technology through the application of our proprietary VGT Turbo and XPI fuel system. The integration of these technologies provides superior efficiency and crisp response to driver command. In essence, the X15 breathes like a medium-bore engine, but delivers big-bore performance. Cummins continues its legacy of innovation by becoming the first to introduce this combustion technology to the commercial truck market.

SmartCoast Technology

SmartCoast improves efficiency while coasting. On moderate downhill grades, the transmission will keep the clutch engaged while shifting out of gear, allowing the engine to return to idle and reducing drag on the vehicle. That conserves vehicle momentum and improves fuel economy.

The transmission automatically shifts into the correct gear at the exact moment that power is needed to maintain road speed, whether you need acceleration or engine braking. SmartCoast alone improves a truck’s fuel economy by 2 percent. An additional feature that works with SmartCoast is Predictive Cruise Control (PCC). Using Global Positioning System (GPS) technology, it previews the road ahead and modifies both the fueling rate and road speed limit, to take advantage of vehicle momentum with such precision that you’ll gain an extra 1 percent in fuel efficiency.

Every X15 Efficiency Series engine will leave the Cummins factory with PCC installed and enabled. Advanced technology such as SmartTorque2, SmartCoast and PCC make the X15 the most fuel-efficient engine in the industry.

Shop our new trucks inventory to find class 8 semi trucks equipped with Cummins engines today!