DEF itself is a solution of 32.5 percent urea and 67.5 percent deionized water. The heat of the exhaust breaks this solution down into ammonia, which reacts with the NOx turning it into nitrogen ...

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

For most diesel-powered engines, DEF is vital so the vehicle performs at its best. Here's what it is exactly and what the acronym stands for.

Diesel exhaust fluid is the primary solution used in NOx aftertreatment. Most diesel vehicles today cannot legally operate without DEF. But what is NOx, and why do fleets need DEF to treat it?

As seen in the following four-minute video, maintenance tips include how to refill the Diesel Exhaust Fluid, or DEF, ... 2025 Chevy Traverse Drive Modes Explained .

Given how important the fluid is, you don't want your diesel-powered vehicle to run on expired DEF. Long-term use of expired DEF can significantly affect the performance of the selective catalytic ...

“DEF is manufactured from an automotive/medicinal grade of urea dissolved in deionized water,” explained Jay Gagnon, senior product manager for BlueDEF diesel exhaust fluid and dispensing ...

GM has issued a service bulletin for a DEF sensor problem fix for the 2020 to 2024 GMC Sierra 1500, GMC Sierra HD, and GMC Yukon involving module recalibration. News Podcast ...

Diesel exhaust fluid, also known as DEF, AUS (from aqueous urea solution), or AdBlue, is used to lower the concentration of NOx in diesel exhaust emissions.Usually, the DEF tank filler is placed ...