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Thomas Built Reports Success With Engine Aftertreatment Adjustment

Some school districts are seeing significant drops in DPF-related maintenance issues after using the "Stay Warm" feature for Cummins diesel engines.

February 23, 2018
Thomas Built Reports Success With Engine Aftertreatment Adjustment

Some school districts are seeing significant decreases in DPF-related maintenance issues after using DPF temperature stabilization in their buses with Cummins diesel engines.

2 min to read


Some school districts are seeing significant decreases in DPF-related maintenance issues after using DPF temperature stabilization in their buses with Cummins diesel engines.

HIGH POINT, N.C. — Some school transportation providers are seeing success using a feature designed to optimize performance in Cummins diesel engines.

Last year, Thomas Built Buses announced that it had begun offering the new feature, known as diesel particulate filter (DPF) temperature stabilization or “Stay Warm.” The new feature is designed to optimize the regenerative parameters of diesel engines, increasing active regeneration and decreasing aftertreatment DPF maintenance issues. Over the past year, Thomas Built dealers have been implementing the Stay Warm feature in diesel school buses across North America.

While some school districts are seeing up to a 75% decrease in aftertreatment-related issues, other school districts now have zero DPF-related maintenance issues, according to Thomas Built Buses.

“We have had phenomenal results with the new Stay Warm feature,” said David Walton, vehicle services coordinator for Prince William County Public Schools in Manassas, Virginia. “We now only have one-off regeneration issues, a dramatic reduction from where we used to be. The minimal issues we have now are not even in the same ballpark as what we’ve experienced in the past.”

In partnership with Cummins, the Stay Warm feature is standard and factory-installed on all Cummins engines with a standard exhaust configuration starting April 11, 2017. Thomas Built dealers can also have the engines programmed with the Stay Warm feature for customers with buses with older Cummins engines (model year 2010 or later).

Patty Waites, the assistant director of transportation for Hamilton Southeastern School District in Fishers, Indiana, was one of the first customers to receive the Stay Warm update.

“A representative of Cummins came by and changed the parameters of all of our buses," Waites said. "Since the parameter change, we have had zero DPF issues. We just love it.”

Some Thomas Built customers are also training drivers on more fuel-efficient driving techniques to further increase the efficiency of their diesel engines.

“Changing the parameters has definitely helped us a lot. We went from six to seven regens a day in the shop to a total of four a week,” said Charlie Turvin, fleet trainer for Loudoun County (Va.) Public Schools. “But changing parameters is not the only change we made in our shop. We also taught our drivers how to reduce idle time, how to handle a regen, and the proper gear to drive in.”

“We are thrilled that fleets are seeing significant improvement in their engine and DPF performance due to the Stay Warm feature,” said Caley Edgerly, president and CEO of Thomas Built Buses. “Diesel is one of the cleanest fuels available today and with this feature, fleets can now experience reduced engine maintenance and costs, as well as fleet downtime.”

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