New Detroit DD8 Engine Revealed
The 7.7-liter medium-duty diesel engine will be offered for the Thomas Built Saf-T-Liner HDX school bus starting in 2018.

The 7.7-liter DD8 medium-duty diesel engine will be offered for the Thomas Built Saf-T-Liner HDX school bus starting in 2018.

INDIANAPOLIS — Daimler Trucks North America (DTNA) unveiled the new Detroit DD8 medium-duty diesel engine at the NTEA Work Truck Show here on Wednesday.
The 7.7-liter DD8, an in-line six-cylinder engine, provides a horsepower range of 260 to 350 and a torque range of 660 to 1,050 lb.-ft.
The DD8 is the second of two new medium-duty engines that will eventually be available for various types of vehicles within DTNA’s brands, including Thomas Built Buses. The first of the medium-duty engines, the DD5, was on display at Thomas Built’s booth at the National Association for Pupil Transportation trade show in November.
“The Detroit DD5 medium-duty engine, as well as the upcoming Detroit DD8 engine, will provide exceptional fuel efficiency, power, proven performance, and reliability as well as the lowest total cost of ownership,” Caley Edgerly, president and CEO of Thomas Built Buses, said in November.
The Detroit DD5 engine will be available for the Thomas Built Saf-T-Liner C2, and the DD8 will be offered for the Thomas Built Saf-T-Liner HDX. The engines will be available for order in 2018. Start of production for both products with the Detroit engines is expected to take place later that year.
DTNA announced in November 2015 a $375 million investment to bring the manufacturing of both medium-duty engines to its manufacturing facility in Redford, Michigan. The facility also produces the Detroit heavy-duty line of engines, as well as transmissions and axles.
The DD8 and DD5 engines will be equipped with the Detroit Connect Virtual Technician remote diagnostics service, which relays fault code details to the fleet by email or notification via the Detroit Connect portal.
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