05 Dec 2018

Diesel Exhaust Fluid

What is Diesel Exhaust Fluid or (DEF)?


Diesel Exhaust Fluid (DEF) is required for diesel engines and helps to control emissions. DEF is a non-hazardous solution that is mostly water. DEF contains 67.5% de-ionized water and the remaining percentage is urea. In fact, it looks just like water. DEF smells a bit of ammonia or like the cleaning supplies you probably have at home.

This “after treatment” approach destroys all of the harmful emissions in the exhaust, after combustion. DEF is injected directly into the stream of the exhaust, not added to the fuel. Diesel Exhaust Fluid sprays into the exhaust stream, and breaks down the gasses into water and nitrogen.

Because DEF is not flammable or explosive, it is classified under transportable fluids with minimal risks. If you spill Diesel Exhaust Fluid on your hands, just wash them with water and soap.


Where can I buy DEF?


High-quality DEF is available to individuals, retailers, wholesalers and directly to fleets in bulk. You can buy DEF at the road side or from retailers in over 2500 different locations across the US, and there are also many in Canada.

Most fueling stations have a DEF pump right beside the diesel fuel pump, so adding DEF can be just as convenient as adding diesel to your vehicle.


How much does DEF cost?


You can purchase DEF in jugs, drums, totes and also in bulk. Note: If your company or fleet needs to purchase DEF in bulk, visit https://www.certifieddef.com/ to see what options they offer.

Keep tabs on the average retail prices and how many locations sell it with the Diesel Exhaust Fluid Tracker. They watch for roadside dispensing options for DEF and for how many locations sell it, so that you can know where it is sold.

The current prices are as follows:

  • $2.82 US / gallon across the United States and sold in 2670 locations
  • $0.80 CDN / litre across Canada in and sold in 253 locations

Diesel Exhaust Fluid (DEF) is important for your vehicle and the environment. The law also requires the use of DEF in diesel vehicles, so be sure to maintain your DEF levels and stay compliant.