What is Diesel Exhaust Fluid (DEF)? What is its use for vehicles?
2 Answers
Diesel Exhaust Fluid (DEF) is an essential product for heavy-duty diesel vehicles to meet China's National IV emission standards. Below are relevant explanations: 1. Definition: DEF refers to an aqueous urea solution with a urea concentration of 32.5% and solvent being ultrapure water. The raw materials consist of specialized urea for vehicle use and purified water. 2. Function: To reduce nitrogen oxide emissions. It can be directly added to the vehicle's DEF tank or filled through a dispensing machine. Generally, filling up to 80% of the DEF tank capacity is sufficient. Using this product can effectively reduce nitrogen oxides and particulate matter in exhaust emissions, decrease air pollution from acidic gases, and improve air quality.
As a veteran truck driver with over a decade of experience, I deal with diesel vehicles daily. Diesel exhaust fluid (DEF) is an essential liquid for SCR systems, specifically designed to treat diesel exhaust emissions. Truck engines emit particularly high levels of nitrogen oxides during operation, and spraying urea solution into the exhaust system helps break down harmful gases. I always keep several barrels of Blue Star DEF in my truck, needing to refill every 300-400 kilometers. If I skip the refill or use inferior products, the truck immediately experiences speed and torque limitations, and in severe cases, it can damage the engine and after-treatment system. For China VI vehicles, skipping DEF usage results in a direct fine of 200 yuan! Remember to use the -35°C antifreeze type in winter—the regular type freezes at -11°C and can clog the entire system.
