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What Is Diesel Exhaust Fluid?

Diesel exhaust fluid (DEF) is an emissions liquid that modern diesel engines require to run accordingly with the U.S. Environmental Protection Agency’s (EPA) emissions standards. It is a non-hazardous solution of one part urea and two parts of de-ionized water. Now, you may be wondering, “how does DEF work?” and “why does the EPA require it for diesel vehicles?” Well, keep reading to find out.

How Does Diesel Exhaust Fluid Work?

Never add DEF to diesel fuel. Instead, it is injected into the exhaust stream by selective catalytic reduction (SCR) technology. We can reduce diesel engines’ harmful nitrogen oxide and particulate matter (PM) emissions by using DEF and SCR technology.

SCR technology is not new. It’s been around for about 50 years. It was first used in the power generation industry to reduce nitrogen oxides from coal-fired power plants. Nitrogen monoxide and nitrogen dioxide (NOx) are dangerous emissions caused by diesel combustion. In a vehicle with SCR technology (most diesel vehicles built after 2010), the exhaust from the engine is first routed through a particulate filter that catches the soot and ash created from burning impure fuel. After the particulate filter, the exhaust travels past a nozzle that sprays DEF into it. The exhaust and DEF then enter the catalytic converter. The DEF and the exhaust urea react with various metallic compounds to convert NOx into nitrogen, water, and carbon dioxide.

When Do You Need to Refill On DEF?

You can refill every time you get an oil change or every 10,000 miles. However, it’s best to check your owner’s manual for the exact distance your vehicle can travel before having to refill. If you don’t refill your DEF in time, eventually, you’ll be unable to start your engine. Don’t worry, though. You’ll receive ample warning from your vehicle’s dashboard before that happens. And, if this does happen to you, all you have to do is refill your DEF, and your engine will start for you without any problems.

Refilling your DEF should be very easy. Most modern vehicles have a DEF inlet stationed next to your gas tank inlet. The cap will be blue. This not only makes the process easy, but every time you fill up on gas, you have a reminder that, at some point, you’ll need to refill on DEF. Some older vehicles, made before manufacturers standardized the location by the fuel tank, will have DEF tanks located in the engine bay or trunk.

Trust us, refilling is not a hassle and will set you back at less than $20. Most DEF bottles come with a nozzle that attaches to the top. This nozzle allows you to fill up on DEF without spillage. If your bottle doesn’t come with a nozzle, make sure you have a funnel on hand to make the process easier. Don’t worry about filling your DEF tank by hand if you drive a big rig. Most truck stops offer DEF in pumps, much like the traditional gas pump.

If you have extra DEF that you would like to store, make sure it’s put in a climate-controlled space and kept in its original container. If DEF gets too cold, it can freeze, and it can degrade your DEF if it gets too hot. Transferring it to another container not specified for DEF storage is also bad for your product, as you risk contaminating your DEF with other substances that can damage your vehicle.

Why Do We Need DEF?

Starting January 1, 2010, the EPA required all medium- and heavy-duty diesel vehicles to significantly reduce engine emissions, particularly NOx and PM. These standards exist to improve air quality. Scientists have linked NOx and PM emissions to various health problems, like respiratory and cardiovascular diseases, aggravation of asthma, acute respiratory symptoms, decreased lung function, and chronic bronchitis. While a vehicle with SCR technology may cost more, it offers greater reliability and longer oil change intervals, adding up to impressive savings over the vehicle’s lifetime.

Get Your DEF With Home Service Oil!

At Home Service Oil, we offer many distribution services for many products. However, if you’re looking for a reliable bulk distributor of DEF, then you’ve come to the right place! Whether you have farm equipment you need to fill or a fleet of vehicles that need to get to work, we can deliver straight to you, offering peace of mind and a guarantee that you’re getting what you need when you need it. Check out our services today!




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