Diesel exhaust fluid (DEF) is an important component of reducing emissions in diesel engines. DEF contains 67.5% deionized water and 32.5% nitrogen-based urea. This solution helps reduce the amount of nitrogen oxide gases that are emitted into the atmosphere. There are numerous benefits of using DEF, as well as some additional things you should know about it.
How DEF Works
DEF is required for Tier 4 emissions regulations, which means most new, large diesel engines must meet these requirements. DEF helps meet these requirements by turning nitrogen oxide gases into oxygen, water, and nitrogen. The fluid is injected into the exhaust stream and works with catalysts to convert the gas into these elements that are harmless to the environment.
Benefits of DEF
DEF is an inexpensive way to improve diesel emissions. Nitrogen oxide emissions are dangerous because the smog they contribute to can cause heart and respiratory problems. In addition to reducing emissions, DEF can actually help with fuel efficiency because it improves horsepower and allows the engine to run more smoothly. Additionally, DEF is easy to obtain from truck stops, gas stations, auto parts stores, and other retailers. It’s easy to use and you can easily calculate how much DEF you’ll use with online diesel exhaust fluid calculators.
DEF generally costs $2-3 a gallon, so it really doesn’t increase operating costs much. Most manufacturers size the DEF tanks so that you refill the DEF tank every time you refuel or every other time you refuel. This simply makes it easier to remember when it’s needed. Most newer machines have a dashboard indicator to let you know how much DEF is in the tank as well. Refilling the DEF tank is made simpler by placing the filling cap on the same side as the fuel tank. However, the DEF filler cap is a different color and smaller diameter of the fuel tank filler tip to prevent fueling mix-ups.
Yearly DEF Consumption
The amount of DEF most off-road vehicles use is equal to anywhere from 2-10% of the fuel that’s burned. It also depends on the make of your engine. There are other factors to consider like exhaust gas recirculation, fluid consumption rates, temperature, and humidity. Cold, humid places require less DEF consumption. You can monitor your usage the first few months and then use an online DEF usage calculator to help you better calculate how much you’ll typically use per year.