• +What is DEF

    DEF is Diesel Exhaust Fluid.

  • +What purpose does DEF serve?

    DEF is used in Selective Catalytic Reduction (SCR) systems to change the Oxides of Nitrogen (NOx) emissions in diesel exhaust to Nitrogen and water. Nitrogen makes up about 78% of the air we breathe every day.

  • +What will occur with my truck if I do not refill the DEF tank?

    Performance degradation to be followed by an inability to start your vehicle will occur if you do not fill the tank.

  • +Does it matter what DEF brand I purchase?

    Yes, it does! Brenward offers an ultra pure, aldehyde-free DEF. Aldehydes are preservatives and known carcinogens.

  • +What does DEF smell like?

    The liquid can have a slight ammonia smell.

  • +What are the benefits of using DEF?

    Diesel engines equipped with SCR using DEF not only meet the 2010 tailpipe standard, but they also deliver significant fuel economy.

  • +Will my vehicle sustain any damage if I accidentally spill the DEF on the engine or other surface?

    DEF can be mildly corrosive to some materials, particularly aluminum, copper and other alloys. It should be washed off with water.

  • +What factors degrade DEF?

    Product should be stored in temperatures between 12º F and 86º F.

  • +What if DEF gets on my hands or in my eyes?

    According to OSHA, DEF is mildly irritating to the eyes and skin. If the liquid should contact either, the DEF should be flushed out/washed off with plenty of clean water. For more health and safety information, refer to: BrenWard Health Information

  • +Why is it necessary to use DEF now, and is it required by law?

    Diesel engines purchased after January 1, 2010, require the use of DEF to meet the EPA 2010 tailpipe standards.
    Yes it is required by law, in diesel engines produced after January 1, 2010, DEF is required for emissions after-treatment.

  • +Are there legal penalties for not using DEF?


  • +Are there any storage considerations/limitations for DEF?

    Yes, since DEF can degrade over long periods of time (>1 year), and at temperatures over 86˚F, long-term storage should be limited, if possible.

  • +Should my DEF tank be emptied if my truck is placed in storage?

    Not required. Vehicle on-board controls are designed to store and handle DEF.

  • +Where can I get more information on DEF?

    Feel free to call or email us and we will gladly answer any other questions you may have.
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