DEF (Diesel Exhaust Fluid) is one of the key elements of the SCR (Selective Catalytic Reduction) process. It is a nontoxic solution of 67.5% purified water and 32.5% urea. When injected into hot exhaust as a fine mist and passed over a catalyst, DEF helps convert NOx (nitrogen oxide) into nitrogen gas and water vapor—two clean and harmless components of the air we breathe. DEF is stable, colorless and odorless, and meets accepted international standards for purity and composition.

In heavy-duty diesel engine applications, antifreeze/coolants are formulated to prevent cavitation and liner pitting in wet sleeve liners. A wet sleeve cylinder liner is a replaceable metal sleeve inserted into a diesel engine block to improve heat transfer and enhance serviceability of heavy-duty engines. It is also considered one of the most common and costly cooling system repairs.