Diesel exhaust fluid, or DEF, is a key component in lowering pollutants emitted from diesel engines, helping to improve efficiency and reduce emissions.

Rislone's DEF Crystal Clean dissolves crystalized urea so your DEF system works as it should.

The U.S.Environmental Protection Agency is working to fix a long-standing headache for diesel truck and equipment operators: power cuts triggered by low diesel exhaust fluid levels.

The U.S. Environmental Protection Agency (EPA) issued new guidance to engine manufacturers on Aug. 12 regarding diesel exhaust fluid (DEF) systems to prevent unnecessary engine shutdowns and power ...

The EPA on Tuesday said new trucks won't derate due to DEF system faults nearly as quickly or severely, and announced plans to modify software on all existing trucks to extend the timing for derates.

Field Work Interruptions: If a tractor runs out of DEF or if the system breaks down, under the now-defunct previous guidelines engine power was greatly reduced, which is known by many farmers as ...