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DEF (Diesel Exhaust Fluid): A Guide for Fleet Operators
What is DEF?
Diesel exhaust fluid is a urea solution that reduces emissions in modern diesel engines. Trucks with SCR systems will not run properly without it.
How much do you need?
DEF use is typically around 2 to 3 percent of diesel consumption. Buying in bulk or by the tote lowers your cost per litre.
Storage tips
Store DEF in a cool, clean, sealed container away from direct sunlight. Contamination can damage your SCR system, so always use fluid that meets ISO 22241 standards.