Detroit Engines: Trusted Performance, Built for What's Next
Since 1938, Detroit Diesel engines have powered the work that builds the world around us. That legacy took a major step forward in 2007, when a new era began with the launch of the DD15®, which was closely followed by the DD13® for regional haul and vocational applications, and the DD16® for severe-duty jobs. Together, this trio formed the foundation of Detroit’s Heavy Duty Engine Platform, proving itself over nearly two decades and more than 1.2 million engines on the road.
Now, building on 87 years of legacy and continuous engineering, Detroit is proud to announce the sixth generation (Gen 6) DD13®, DD15®, and DD16® engines. With production beginning in January 2027*, Gen 6 sets a new benchmark for efficiency, performance, reliability, and system integration. It’s innovation that stays true to the proven power that Detroit customers already trust.
*Production of the DD13 and DD15 will start in January 2027, while the DD16 will follow with all the same upgrades in 2028.
Engines Designed for Efficiency
Detroit engines have long been known for efficiency, and Gen 6 takes it another step further. Through a combination of proven and advanced technologies, key efficiency enhancements include:
- Redesigned fuel rail delivers fuel at a consistently higher pressure, eliminating the need for amplified local injections. The simplified design ensures strong, more consistent fuel flow.
- Enhanced asymmetric intake port & fuel injectors increase swirl in the cylinder and create a cleaner, more efficient air-fuel mixture. This enables triple-front combustion, which reduces heat loss and compression work.
- Miller timing on the camshaft reduces the compression work while increasing the compression ratio.
- Oil-lubricated fuel pump & variable displacement oil pump reduce parasitic load, easing the engine's workload and extending it's lifespan.
- Optimized combustion elements, including a 12-volt thermostat, increased swirl, and a small piston bowl, all work together to maximize the use of fuel.
For more details, keep reading about Gen 6 Engines.
Performance Where and When It Matters
Gen 6 engines deliver stronger, more confident performance across the wide range of conditions drivers and operators face every day. Horsepower and torque ratings have been optimized to support greater down speeding, providing more usable power at lower engine speeds.
This translates to smoother acceleration, improved control, and better capability when hauling heavy loads, climbing grades, merging into traffic, or operating across varied terrain. Engine brake performance has also been enhanced, giving drivers more control during downhill stretches while reducing wear on service brakes.
Here’s how the Gen 6 Engine ratings stack up:
|
Model |
Horsepower Range |
Torque Range |
|
DD13 |
410–525 HP |
1450–1850 lb-ft |
|
DD15 |
425–505 HP |
1650-1900 lb-ft |
|
DD16 |
560-605 HP |
1850–2050 lb-ft |
Additional performance improvements include:
- A refined turbocharger with updated compressor geometry and a new wastegate actuator. This gives the engine a faster response at low speeds and consistent performance at higher altitudes. When operators are hauling through mountain passes or working in regions with thinner air, they can rely on power that holds up and flexible control over a variety of jobs.
- A thermal control valve that helps the aftertreatment system reach optimal operating temperature faster. This significantly reduces the need for parked regenerations and gives operators more momentum on the job by minimizing unplanned downtime.
Together, these enhancements deliver a more capable and responsive driving experience. Operators can stay productive in tough conditions, proving that cleaner technology doesn’t come at the expense of power.
A Reliable Foundation, Refined for the Future
Detroit couldn’t have built its legacy without reliability at the core of engine design. The Detroit DD Engine series was originally engineered to meet customer demands while addressing evolving emissions regulations. Now, Gen 6 Detroit engines deliver greater durability and dependability while complying with 2027 Environmental Protection Agency (EPA) emissions standards.
Gen 6 engines are built on the foundation of known and proven technologies. This simplifies the transition for fleets, operators, and technicians alike. As the engine and aftertreatment system stay updated to align with current sustainability practices, Detroit engines are refined with the least possible complexity, keeping the same footprint that our customers know and trust.
Reliability is reinforced through smart design choices that deliver increased power, torque, and compression pressures without requiring heavier or bulkier engines. A simplified and more robust Exhaust Gas Recirculation (EGR) system further improves reliability, while service intervals and voltage architecture remain unchanged for a seamless transition to the next generation.
Familiar Aftertreatment Packaging, Ready for 2027 Emissions Standards
The 1-Box aftertreatment system builds on proven Selective Catalytic Reduction (SCR) technology, maintaining compatibility with back-of-cab body equipment for straightforward integration into existing truck designs. Customers benefit from a system that supports emissions compliance and fuel efficiency while minimizing added complexity or changes to their vehicles.
As emissions regulations continue to evolve, staying ahead of the curve requires thoughtful integration, and Gen 6 does so without the need for a complete redesign. This suite of engines complies with 2027 Environmental Protection Agency (EPA) emissions standards while building on proven Detroit technology.
A key enabler is the newly redesigned aftertreatment system, which uses trusted components in a smarter and more efficient configuration. The system achieves full emissions compliance without changing Diesel Particulate Filter (DPF) part numbers, helping simplify service and maintenance while maintaining compatibility with existing vehicle layouts.
To further reduce nitrogen oxide (NOx) emissions—particularly during cold starts—a compact Pre-Selective Catalytic Reduction (Pre-SCR) system is positioned closer to the engine. When paired with a thermal control valve, this integrated approach enables faster warm-up, increases passive regeneration frequency, and improves overall aftertreatment system efficiency.
Smart and Safe Powertrain Solutions, Leveraging the Detroit Difference
Detroit delivers a fully integrated powertrain designed to combine performance, reliability, and efficiency for fleets. Engines, transmissions, and axles work seamlessly together for greater responsiveness across a range of applications.
Additionally, safety is enhanced through the Detroit Assurance® Suite of Safety Systems. Advanced technologies like Side Guard Assist and Active Brake Assist help mitigate collisions and offer greater confidence on the road or jobsite. Meanwhile, Detroit Connect provides advanced fleet management tools and a growing portfolio of connected services, giving fleet managers insights to improve efficiency, uptime, and overall performance.
By combining fully integrated systems with trusted technology, Detroit ensures customers enjoy a powertrain that’s not only capable and efficient but also smart, safe, and ready for the demands of today’s fleets.
The Next Generation of Industry-Leading Power
Detroit has never stopped refining what it started. Built on over 87 years of proven legacy and 20 years of Detroit innovation, the Gen 6 engines are more efficient and trusted than ever, complying with 2027 emissions standards without compromising power, performance or reliability. These engines prove that smart integration, not added complexity, is the path forward.
To learn more,
- Explore product details and spec your Freightliner or Western Star with the DD13, DD15, or DD16.
- Find your nearest dealer with our Dealer Locator.
- Sign up for our email newsletter to get the latest updates and insights sent straight to your inbox.
Note: Production of the DD13 and DD15 will start in January 2027, while the DD16 will follow with all the same upgrades in 2028.