Related: Thomas Built Buses Delivers First School Bus With DD5 Engine
Thomas Built Buses, Detroit Diesel Expand DD5, DD8 Warranty Coverage
The new Detroit DD5 and DD8 engines now include an extended warranty solely for the two engines' aftertreatment systems.

The new Detroit DD5 and DD8 engines now include an extended warranty solely for their aftertreatment systems. Shown here is Thomas Built Buses' Saf-T-Liner C2 school bus equipped with the Detroit DD5 engine. Photo courtesy Daimler Trucks North America

HIGH POINT, N.C. — Thomas Built Buses along with Detroit, a supplier of heavy and medium-duty diesel engines, have expanded the warranty options for the Detroit DD5 and DD8 engine aftertreatment systems.
Currently, a standard warranty of five years/100,000 miles, including 100% parts and labor, covers both the engine and the aftertreatment system of the DD5 and DD8 engines, according to a news release from Daimler Trucks North America, the parent company of Thomas Built Buses. Now, customers have the option of adding an extended warranty for just the aftertreatment system.
“The aftertreatment systems of our new Detroit DD5 and DD8 engines are one-of-a-kind with some of the greatest fuel efficiency in the marketplace and variable cam phasing, which in the end, cause less wear and tear on the aftertreatment system," said Caley Edgerly, president and CEO of Thomas Built Buses. "This results in far less faults and a system that requires far less maintenance than conventional aftertreatment systems."
Coverage options vary but can cover up to 10 years unlimited mileage, according to Daimler. Detroit’s aftertreatment extended warranty will only cover the aftertreatment system. Additional engine warranty coverage is also available to cover progressive damage to the engines.
For more information about Thomas Built Buses or warranties, customers can contact their local dealer.
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