Prevents Crystals in DEF systems - Designed to work with DEF for diesel trucks, this additive helps prevent white crystal buildup in SCR systems, protecting injectors, pumps, and sensors from costly damage. DEF Additive Cleaner for Reliable Performance - This DEF additive cleaner is designed for diesel exhaust fluid systems to support peak SCR performance and long-term reliability of sensors, injectors, and other critical components. Protects SCR System Components - Formulated to lubricate and stabilize DEF fluid for diesels, this additive helps reduce corrosion, crystal buildup, and freezing in the SCR system—especially in cold weather. DEF System Cleaner That Helps Address Trouble Codes - This DEF system cleaner helps maintain a clean SCR system, reducing the risk of trouble codes like P20EE, P204F, and P207F caused by buildup or crystallization in diesel exhaust fluid components. Easy-to-Use DEF Additive for Diesels - Add 1 oz per 2.5 gallons of DEF directly into the tank during each fill-up. This DEF additive for diesels treats up to 20 gallons per bottle and helps maintain optimal SCR performance.