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Ordering now available for the most efficient, reliable, clean diesel engine on the market. The “DD5” and “DD8” are finally here! Contact your sales rep for more details.

From: HIGH POINT, N.C. – (July 24, 2018) – Thomas Built Buses is now accepting orders for the Detroit™ DD5™ and DD8™ engines, the most efficient, powerful, reliable and clean diesel school bus engines in the market.

“We’ve been waiting for this day for a long time,” said Caley Edgerly, president and CEO of Thomas Built Buses. “Both of these engines were developed from the ground up specifically for the medium-duty industry. These clean-sheet designed engines aren’t new. They are only new to the school bus industry. This proprietary engine platform was launched in Europe in 2013. Today, more than 90,000 engines are running on this platform with great success, including best-in-class fuel economy and maintenance intervals, proven power, performance and reliability, lower emissions and a lower cost of ownership. We cannot wait to see how these engines will revolutionize school bus fleets across North America.”

The Detroit DD8 engine is a 7.7L inline 6-cylinder medium-duty engine with specific development for the Thomas Built Buses Saf-T-Liner® HDX. It boasts a horsepower range of 260-300HP and a torque range of 660-860 lb.-ft. The DD5 engine is a 5.1L inline 4-cylinder engine adapted specifically for the Thomas Built Buses Saf-T-Liner® C2. It offers a 200-240 horsepower range and a torque range of 560-660 lb.-ft.

Both the DD5 and DD8 boast power and best-in-class fuel economy thanks to a state-of-the-art design that allows usable power and torque to be reached at lower engine speeds. School districts can expect at least a three percent improvement in fuel economy compared to other diesel engines in the category.

Longer service intervals also are a key differentiator, with some of the longest service intervals in their class with oil and filter change intervals up to 45,000-miles (or either 18 months or 1,500 hours, whichever comes sooner.) The Detroit engines feature top-load oil and fuel filters for easier serviceability.

Both engines come with, Detroit™ Connect Virtual Technician℠ remote diagnostic service. Virtual Technician will help transportation directors make informed maintenance decisions so buses are serviced only when needed. Virtual Technician, with the backing of the experts at the Detroit Customer Support Center, provides access to in-depth diagnostic information to get buses repaired as quickly and accurately as possible, improving uptime.

Both the DD5 and DD8 were built to produce fewer emissions, so they meet 2017 greenhouse gas (GHG17) standards and will continue to meet emissions standards through 2020. Both engines also employ innovative technology such as a variable cam exhaust phasing, which allows additional heat to the exhaust stream. This enables efficient operation of the school bus’s aftertreatment system in low-speed stop-and-go operations, virtually eliminating the aftertreatment issues of previous diesel engines.