Overdrive sister publication CCJ recently had the opportunity to get a first-hand look at Detroit Diesel’s newest engines, the company’s sixth-generation engine platform.
As reported by CCJ Chief Editor Jason Cannon, Detroit’s lineup features updated DD13, DD15, and DD16 engines. All will meet the Environmental Protection Agency’s 2027 regulations, requiring nitrogen oxide (NOx) emissions slashed by more than 80%, and particulate matter by 50%.
Cannon and Detroit’s Steve Collins run through the updated platform in the video above, showing just how the engine maker is doing it.
“In Detroit's case, it was important to keep those technologies familiar,” Cannon said. That includes a selective-catalytic-reduction (SCR) pre-treatment system that’s positioned upstream from the primary aftertreatment system. “This helps the engine reach operating temperatures faster, a critical factor in reducing emissions during cold starts and minimizing the need for parked regens.”
[Related: EPA 2027 diesel emissions regs: Class 8 truck price hikes in the offing]
That also means the system introduces diesel exhaust fluid (DEF) ahead of the primary system, taking advantage of exhaust heat before the aftertreatment system gets to operating temperature.
For Detroit, the hardware and functionality are nearly identical to the SCR that’s been in use since 2010, Cannon noted. “The gen-six pre-SCR system sits on top of the current one-box footprint, preserving existing chassis space with no impact on back of cab packaging.”
Additionally, a thermal control valve that was only on the gen-five DD13 is now rolling out to all of the sixth-generation DD-series engines. That valve “articulates to increase the heat output from the engine, improving aftertreatment performance,” Cannon said. “It also enables faster aftertreatment warmup, faster regens, more passive regens and low-duty cycle operations," and reduced exhaust gas emisisons. "It virtually eliminates the need for parked regens for most applications.”
See and hear more about the updated engines and their emissions systems in the video up top, or in CCJ's coverage here.
[Related: Detroit readies rollout of new 2027 engines]
Jason Cannon: The model year 2027 will bring with it new diesel emission standards that current generation engines simply can't meet. So you know what that means? We get new engines and new after treatment solutions. I'm CCJ editor Jason Cannon and join me for a quick look at Detroit Diesel's six generation DD series engines.
Steve Collins: So on the Gen six platform, we're introducing a new oil lubricated high pressure fuel pump. That oil lubrication is an efficiency gain in and of itself. That pump has to work less hard to provide supply fuel to fuel system. That high pressure pump also enables a even higher pressure common rail here, so up to 2,500 bar on the high pressure common rail. That's a change from the Gen five. We used to have a lower pressure rail here and amplification within the ejectors themselves. But this higher pressure rail enables us to use simple non-amplified injectors in cylinder itself with over the course of the lifetime provider more and continuous performance and more consistent performance over time. Going back to the oil lubricated high pressure fuel pump is also a bit of a robustness gain too. Frits don't always have the ability to perfectly monitor the quality of fuel that they have access to.
And if we're utilizing previously a fuel lubricated hypers or fuel pump, it was a little bit more susceptible when you didn't have super high quality fuel. So an oil lubricated pump helps with that robustness factor as well. So on the hot side of the engine, we've got some enhancements to the turbocharger. We're using that same asymmetric turbo from the previous generation system with some optimizations and enhancements. First thing we're bringing over that efficient ball bearing design that was previously only utilized in the efficiency ratings of the previous generation, but we're applying that across the board to all displacements and all engine ratings. That fall bearing design, one more efficient, it can spool up more quickly, which leads to better throttle response too. We're pairing that with a simple wastegate, and that wastegate really allows us to really precisely control the airflow even more. And so think about the various different types of applications that these engines are utilized in.
And something especially like high altitude. That wastegate combined with that ball bearing design turbo allows us to even precisely control air more precisely to allow consistent performance and spool up even at high altitudes, which is really important for our customers operating at those higher elovations. At the Bahat said, that's pretty much it.
Jason Cannon: EPA next year will tighten tailpipe NOx emissions to a level 80% plus below the current standard and reduce the particulate matter limit by 50%. To meet these new standards, truck and engine OEMs will turn to next generation technologies. In Detroit's case, it was important to keep those technologies familiar. For its Gen six DD lineup, Detroit will utilize a pre- SCR system positioned upstream of the primary after treatment system, this helps the engine reach operating temperatures faster, a critical factor in reducing emissions during cold starts and minimizing the need for parked regions. Since the pre-SCR system introduces death ahead of the primary after treatment, it takes advantage of exhaust heat before the ATS gets to operating temperature. Hardware and functionality are nearly identical to the SCR in use since 2010. The Gen6 pre-SCR system sits on top of the current one-box footprint, preserving existing chassis space with no impact on back of cab packaging.
That's an advantage for vocational customers and truck equipment manufacturers. A thermal control valve introduced on the Gen five DD13 is being rolled out to all Gen6 engines. It articulates to increase the heat output from the engine improving after treatment performance. It also enables faster after treatment warmup, faster regions, more passive regions and low duty cycle operations, lower exhaust gas emissions, and it virtually eliminates the need for parked regions for most applications. The same asymmetric turbo that Detroit first launched in 2014 has been further enhanced to improve responsiveness and efficiency while innovative thermal management features reduce regeneration frequency. More responsive and consistent airflow from the turbo helped unlock three new power ratings. Vocational customers, specifically those looking for a 500 horsepower engine but weren't ready to take the leap to an 1850 foot pound of torque can get a DD13 with 505 horsepower and 1750 foot pounds.
The DD15 can be spec with 425 horsepower and 455 horsepower. That's paired with 1,900 foot pounds of torque enabling greater downspeeding capabilities. Otherwise, the power ratings from the gen five models remain unchanged for gen six. That's up to 525 horsepower and 1850 foot pounds for the DD13, up to 505 horsepower and 1850 foot pounds in the DD15 and up to 605 horsepower and 20 50 foot pounds for the DD16. The new engines will be compliant with a new diesel engine oil category set to debut next year. Detroit's not yet decided what the factory fill will be for the Gen six line, but Detroit was the first OEM to use the current FA4 engine oil as a factory fill for its added benefits. An added bonus is that the Gen six DD line will meet the 2027 emission standards without changing service intervals. The Detroit Gen six DD13 and DD15 engines will be available in January of 2027.
DD16 production kicks off the following January of 28.
