Thomas Built to Debut First Type D School Bus With Detroit DD8 Engine

Posted on June 25, 2018
The Detroit DD8 is a 7.7L in-line six-cylinder medium-duty engine with specific development for the Thomas Built HDX school bus.
The Detroit DD8 is a 7.7L in-line six-cylinder medium-duty engine with specific development for the Thomas Built HDX school bus.

HIGH POINT, N.C. — Thomas Built Buses will unveil the first Saf-T-Liner HDX school bus equipped with the new Detroit DD8 engine next month, the company announced on Friday.

The debut will take place at the STN Expo in Reno, Nevada, on July 17. The DD8 is a 7.7L in-line six-cylinder medium-duty engine with specific development for the Thomas Built HDX Type D school bus.

The new diesel engine provides a horsepower range of 260 to 350 and a torque range of 660 to 860 lb.-ft. It features top-load oil and fuel filters and up to 45,000-mile oil change intervals, according to the manufacturer.

The DD8 is the second of two new Detroit medium-duty engines that will be available for various types of vehicles within Daimler Trucks North America’s brands, including Thomas Built Buses. The first of those medium-duty engines, the DD5, was on display in a Thomas Built Saf-T-Liner C2 school bus at the 2017 North American Commercial Vehicle show in Atlanta in September.

The DD8 engine features a fixed-geometry turbo design, along with an integrated engine brake option. According to the manufacturer, the engine’s advanced common rail fuel system optimizes each injection event to minimize fuel consumption, resulting in a fuel efficiency increase of at least 3% compared to other diesel engines in the category.

The DD8 meets 2017 greenhouse gas standards and will continue to meet emissions requirements through 2020, Thomas Built Buses said. Also, the DD8 utilizes technology such as variable cam exhaust phasing, which allows additional heat to the exhaust stream, reportedly enabling efficient operation of the aftertreatment system in school buses in low-speed stop-and-go operations.

“We are so excited to debut this new engine in our Saf-T-Liner HDX,” said Caley Edgerly, president and CEO of Thomas Built Buses. “There is nothing like this engine in the market today, and we cannot wait for our customers to experience how clean, fuel efficient, and easy to maintain this engine is. Our partners at Detroit have truly engineered the best engine for the industry today.”

Like the DD5, the DD8 comes with the Detroit Connect Virtual Technician remote diagnostic service.

The Detroit DD5 and DD8 engines will be available for order from any Thomas Built Buses dealer starting later this year.

Related Topics: diesel, engines, Thomas Built Buses

Comments ( 2 )
  • Lavinia Levaula

     | about 2 years ago

    please can I have your full schedule for school bus drivers training and mechanic training. Your help is very much appreciated.

  • See all comments
More Stories
The NCST’s Steering Committee and writing committees are preparing for the 2020 Congress. Murrell Martin (shown left) and Bill Loshbough are shown here leading a discussion at NCST 2015.

NCST Gears Up for 2020

The National Congress on School Transportation Steering Committee firms up plans and writing committees are researching requests for procedures manual changes. The Congress will meet in Des Moines, Iowa, in May.


Oil Change System

Parker Hannifin’s QuickFit Oil Change System is designed to alleviate the logistical challenges associated with the oil change process.


Digital Vehicle Lift Search Tool

The digital “Find My Lift” tool from Rotary Lift allows users to search, sort, and browse for a vehicle lift that meets their specific needs.


EGR Coolers for Diesel Engines

Bullet Proof Diesel's EGR coolers feature H-Core technology that allows for the natural expansion and contraction of cooling tubes inside the cooler.

Francine Furby, the director of transportation for Fairfax County Public Schools, says that the district’s discipline-tracking system “fosters a partnership with the schools and strengthens their support of our drivers.” Photo courtesy Fairfax County Public Schools

Virginia District Bolsters Driver Support for Success

Fairfax County Public Schools backs its 1,325 drivers with a discipline-tracking system for better follow-up and puts driver supervisors on the road to assist as needed. Additionally, fleet upkeep is boosted with county-employed technicians.

Be the First to Know

Get the latest news and most popular articles from SBF delivered straight to your inbox. Stay on top of the school bus industry and don't miss a thing!