Exhaust Aftertreatment System (EAS) PI / CHU, AN / CXU, GR / GU, TD Standard System View W2029933 1. Selective Catalytic Reduction (SCR) Catalyst 3. Aftertreatment Diesel Particulate Filter (DPF) 2. Aftertreatment Diesel Exhaust Fluid (DEF) Dosing Valve 4. Aftertreatment DEF Tank DEF is a reactant that's key to the SCR process. It's a nontoxic, ultra-pure solution of urea and ultra-pure water. Urea is a compound of nitrogen that turns to ammonia when heated. It is used in a variety of industries, perhaps most commonly as a fertilizer in agriculture. The fluid is non flammable, and is not dangerous when handled as recommended.
However, it is highly corrosive to certain metals, especially copper and brass. Read the separate section concerning the handling of DEF solution. GHG17 ClearTech One One box EATS. W2116209 Mack Body Builder Instructions PI / CHU, AN / CXU, GR / GU, TD, LR, TE / MRU USA141023213 Date 2.2018 Body Builder; Engine, MP7, MP8, and MP10 Page 12 (40) All Rights Reserved