For RVers who tow with diesel trucks or drive diesel motorhomes, this policy change offers more flexibility during DEF system issues. It doesn’t eliminate the need for DEF or emissions compliance.

“We have heard loud and clear from small businesses across the United States that the current DEF system is unacceptable," EPA Administrator Lee Zeldin said.

Zeldin’s plan would not completely eliminate DEF systems, but would significantly extend the amount of time between when the system fails and when machinery capacity is reduced. U.S. Small ...

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The Environmental Protection Agency (EPA) has issued new guidance to diesel engine manufacturers designed to prevent sudden power loss due to DEF systems.

EPA’s new guidance, he said, empowers manufacturers to revise their DEF system software in existing vehicles and equipment “to prevent sudden, severe derates and eliminate abrupt shutdowns ...