DEF Application for Vehicle Emission Reduction
November 19, 2015
Ryan performs a regular service on a BMW 35d X5, with an oil change, filter, and windshield washer fluid. He also topped off the Diesel Exhaust Fluid (DEF) fluid, used in diesels for environmental reasons. Used in BMW’s Selective Catalytic Reduction (SCR) systems on diesel engines, DEF is comprised of a high-purity synthetic urea and deionized water mixture that improves emissions and fuel economy.
Injected into the exhaust stream with a specialized dosing module, DEF’s water vaporizes, leaving ammonia molecules en route to the catalytic converter; once there, it converts NOx molecules into harmless nitrogen and water vapor—making for cleaner emissions.