Six cylinders of industry-leading power

The DD15® engine builds upon the Detroit heavy-duty engine legacy to bring efficiency and performance to the next level. Offering the best of the best in diesel engine technology and engineering, this next generation of the DD15 provides unmatched reliability for your semi trucks.

The DD15 engine touts impressive power ratings, an innovative aftertreatment system and other key features to increase efficiency, durability and performance. Designed with enhanced downspeeding for better fuel economy and a swirl piston design for maximum combustion, the DD15 is up to 3% more fuel efficient than our previous model.

Detroit provides a wide range of new vehicle engines compliant with EPA, CARB emissions, GHG, and OBD requirements. Please consult your local dealer to ensure the selection of a product that meets your specific needs.

Brochures and Videos Maintenance Intervals and Warranties

1550-1850 lb-ft

Torque Range

425-505 HP




The DD15 engine has been significantly redesigned with innovative new features, building on the legacy of the most popular Class 8 diesel engine in North America.

More Specs


The best 6-cylinder diesel engine available in the heavy-duty commercial truck market just got even better. The DD15 builds upon proven Detroit® technology to offer industry-leading efficiency, performance and durability. Key design features include:

  • Better combustion for better fuel economy
    • Ultra-high compression ratios paired with a new swirl piston design create better combustion—and up to 3% better fuel economy. Now more than ever, the DD15 has continued to prove itself as the industry leader, and one of the most efficient 6-cylinder diesel engines for sale in the market.
  • Versatility to be used in a wide range of applications
    • New power ratings and greater application coverage make this diesel engine powerful and durable - no matter what job it needs to do.
  • Enough power to get payloads moving quickly
    • A Ball Bearing Simple Geometry Turbo allows peak power and torque to be reached faster, which gets payloads moving without compromising efficiency.
  • Shorten regen cycles with new aftertreatment system
    • The innovative Thermocoasting feature prevents aftertreatment system cool down during coasting and shortens regen cycles. This feature is one more way Detroit has continued to develop cutting-edge innovation on diesel particulate filters and aftertreatment systems, with the goal of decreasing potential ATS problems and increasing uptime.
  • Greater reliability than ever before
    • The DD15 engine offers less complexity and more durability in many of its key components to achieve an even higher standard. The DD15 is already one of the most reliable diesel engines ever made, this generation builds upon that legacy with expertly engineered improvements in engine technology.
  • Longer maintenance intervals
    • A new aftertreatment system is able to do more with less space, increasing ATS maintenance intervals.
  • Detroit’s trusted service and technology

Model Options

Designed for a range of on-highway and vocational applications.

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Detroit Connect Virtual Technician remote diagnostic system

If maintenance issues come up while on the road, you can count on Detroit Connect Virtual Technician®. With Virtual Technician, you are notified within minutes when your trucks experience a fault event, the severity of the fault, where and how to best fix the issue causing the fault so you can make informed service decisions.

Keep running

With the longest service intervals in its class and an easily serviceable design, the Detroit DD15 lowers your cost of ownership by decreasing your time in the shop. With oil and fuel filters positioned above the frame rails, you'll be back in the driver's seat fast.


Sharing common service operations and parts with the DD13 and DD16 ensures that trained technicians are ready to serve you and your DD15 at any of our 800+ authorized Detroit dealers across the highways and back roads of North America.