Diesel exhaust fluid (DEF) is essential for keeping modern diesel engines compliant with emissions laws and running efficiently. But ignoring your DEF tank or using poor-quality fluid can lead to limp ...

The short answer to why Diesel Exhaust Fluid doesn't work in the cold: It freezes at 12 degrees Fahrenheit. Comprised primarily of deionized water and urea, DEF serves to help make large diesel ...

Diesel engines across agriculture, trucking and construction have been sidelined by a tiny part that was supposed to keep the air cleaner. After years of complaints about failure-prone diesel exhaust ...