Diesel Exhaust Fluid (DEF) is a highly pure aqueous urea solution made of 35.5% urea and 67.5% de-ionized water. DEF has been used in diesel burning vehicles to meet the 2010 Environmental Protection Agency Tier 2 emission standard. Below is a comprehensive list of the Frequently Asked Questions from other customers that captures and most of the questions you might have about Diesel Exhaust Fluid.

How does DEF work?

DEF helps to keep your truck running. Nowadays, many diesel engines incorporate Selective Catalytic Reduction technology to meet the 2010 EPA Emission Standard. DEF is used in on-road diesel vehicles manufactured from the beginning of 2010 to convert Nitrogen Oxide (NOx) into Nitrogen and water molecules, reducing harmful nitrogen oxide emissions.

Why does my equipment need DEF?

Aside from reducing nitrogen oxide emissions from SRC systems found in all Final Tier4 diesel engines, DEF also helps your equipment to run with maximum efficiency; hence reducing fuel consumption and lowering costs for you.

IS DEF harmful to humans?

Diesel Exhaust Fluid is not toxic or harmful. Compared to other fluids used in a diesel engine such as brake fluid and anti-free, DEF is the least hazardous. However, it corrodes some metals such as copper, zinc, aluminium, and carbon steel. Thus, you should avoid storing it in containers made of these materials.

How should I use DEF?

Although the name might imply it, never use DEF in diesel fuel tanks. This fluid should only be used in dedicated DEF tanks, which usually, have smaller openings than fuel tanks and a blue cap, so they are easily identifiable.

How much DEF will my truck use?

This is dependent on the truck’s tank and the dosing rest chosen by the manufacturer. The size of DEF tanks ranges from 6 to 30 gallons. A typical diesel truck goes for roughly 300 miles on one gallon.

How often do I have to refuel DEF?

How often you refuel depends on the size of your fuel tank. DEF consumption rates fall between 2-4% of your diesel tank consumption.

Does DEF freeze?

DEF has a large portion of de-ionized water which becomes crystalline at 12⁰F (-11⁰C). If it gets frozen in your truck, its heating methods will thaw the fluid. Frozen DEF does not affect performance, and little is consumed at low temperatures since cold engines emit little NOx.

What should I do in case of a spill?

In case you make a small spill, you can clean it with water or wipe it up with non-combustible absorbent material such as sand. Spills on concrete and masonry should be cleaned up as soon as possible since DEF is harmful to them. Always prevent large spills from entering confined places such as waterways and sewers. Additionally, do not return spilled DEF into its original container for re-use.

Do not keep your DEF at temperatures above 86⁰F (30⁰C). Buying DEF anonymously from online stores might lead to other questions like why is my VPN not working? If you have more questions about DEF, do not hesitate to ask!