About DEF

Diesel Exhaust Fluid (DEF) is a new product required by many heavy-duty trucks, pickups, SUVs and vans delivered after January 2010. DEF is used to destroy harmful emissions in the exhaust and meet the latest Environmental Protection Agency (EPA) environmental standards.

DEF is non hazardous,consisting of 67.5% de-ionized water and 32.5% urea, and it is used in combination with Selective Catalytic Reduction (SCR) technology. It is sprayed into the exhaust and combines with a catalyst to break down NOx (a harmful pollutant) into nitrogen and water.

In January 2010 emissions legislation went into effect, requiring diesel vehicles to significantly reduce harmful emissions of NOx and particulate matter. A good way to meet these standards is to use SCR and DEF. The trucking industry has been split by this latest piece of rulemaking, with manufacturers pursuing two technology pathways. Daimler, PACCAR, Volvo, Mack, Isuzu, Hino, Ford, GM and others are using SCR, while Navistar has decided to do it alone and use an extension of its 2007 MaxxForce EGR technology.

SCR technology offers many benefits, most importantly great fuel efficiency. On top of this, owners of SCR vehicles will enjoy greater reliability and a longer oil change interval, all of which adds up to impressive savings over the life of the vehicle.