Detroit, Daimler Truck North America’s powertrain brand, has unveiled its Gen 6 heavy-duty engine portfolio, including the DD13, DD15 and DD16. The new engines are designed to meet the EPA’s 2027 emissions standards and will be available across Freightliner and Western Star heavy-duty truck models.
According to David Carson, senior vice president of sales and marketing at DTNA, the Gen 6 platform builds on Detroit’s legacy of performance and reliability while preparing customers for the upcoming regulatory transition.
The Gen 6 engines feature a redesigned and simplified fuel system that eliminates amplified injection and delivers higher, stronger and more consistent fuel flow. Updates also include an asymmetric intake port and new fuel injectors intended to improve air-fuel mixing and combustion. Detroit has incorporated Miller timing on the camshaft to reduce compression work and improve overall efficiency.
To meet 2027 NOx requirements, the engines include a pre-Selective Catalytic Reduction (pre-SCR) system positioned upstream of the primary aftertreatment system. The company says the system helps reach operating temperature quickly and reduces the need for parked regenerations. A new wastegate actuator is designed to improve braking performance and gradeability, particularly at higher altitudes.
Detroit stated that the aftertreatment system preserves existing chassis space with no impact on back-of-cab packaging, an important consideration for vocational applications and equipment manufacturers.
The DD series, part of Detroit’s Heavy-Duty Engine Platform introduced in 2007, has progressed through multiple generations to meet tightening emissions standards. The Gen 6 DD13 and DD15 engines will be available beginning in January 2027, with Gen 6 DD16 production scheduled to begin in January 2028. Detroit manufactures its engines at its Redford, Michigan campus, supported by a recent $285 million investment tied to Gen 6 production.
