What Is Diesel Exhaust Fluid And How Does It Work?

We get a lot of questions about DEF and how to use it effectively on your forecourt, so we asked the expertise of Danny Seals, a forecourt solutions expert, to provide us with some simple answers.

What is DEF?

DEF is a urea-water solution that is injected into the exhaust stream of diesel automobiles to convert NOx gases (harmful emissions) into nitrogen and water. Vehicle manufacturers introduced a Selective Catalytic Reduction (SCR) technology to meet EPA emissions limits in 2010. This is a strategy to achieve the requirements without sacrificing engine performance or fuel economy. DEF isn’t a fuel additive, and it’s kept in its own tank.

Who needs DEF, why?

DEF is required for medium and heavy-duty vehicles equipped with diesel engines manufactured after 2010. To meet emissions rules, the vehicle is configured to inject DEF into the exhaust stream. The engine performance will be diminished and lower speeds will be imposed if the vehicle is allowed to run out of DEF.

What are the different delivery modes of DEF?

DEF is available in a variety of forms. A driver can purchase jugs/containers in a variety of sizes. This necessitates the driver physically transferring the DEF into the car. When installed, DEF can also be dispensed into the vehicle using a fueling dispenser.

Which retailers should offer DEF and what indicators can they use to decide?

Because there is such a vast population of automobiles on the road, DEF is an excellent product for all c-stores to offer. Retailers who sell diesel at their gas stations can utilize the volume sold to estimate the number of diesel customers they have. DEF is required by the majority of today’s heavy-duty trucks. Locations with a separate large truck filling station might think about putting DEF in the dispensers. Because they buy DEF in quantity to keep in their tanks, this results in higher profit margins. Some places that sell a lot of diesel on their forecourt should also consider a dispenser option.

How can Gilbarco help retailers get into DEF?

Since the inception of DEF requirements, Gilbarco has been the industry leader in DEF dispensers. Over the years, we’ve worked with large stores to provide dispenser functionality, and we’ve established the industry standard for this service. Gilbarco assists merchants in entering the DEF dispensing market by providing factory-installed options and retrofitting existing dispensers where DEF is stored in bulk.

What happens when you run out of diesel exhaust fluid?

Vehicle makers must implement procedures to ensure that vehicles cannot run without Diesel Exhaust Fluid, according to the US Environmental Protection Agency (DEF). The driver of a vehicle receives a succession of alerts on their dashboard displays before the DEF tank runs out (much the same way as if they were running low on diesel). In general, an amber warning bulb will illuminate when the DEF tank level drops below 10%, flashing at 5%, and solid amber warning light will illuminate when the DEF tank level dips below 2.5 percent.

The engine’s power is lowered, a solid red warning is displayed, and the vehicle’s speed is limited to 5 mph until the DEF tank is refilled if the truck is allowed to run out of DEF.

Is DEF fluid made from urine?

Because urine is not made of diesel exhaust fluid, urinating in your SCR system will result in you having to pay a lot of money to clean and replace engine components once they’ve been contaminated. Following the deductive premise that urine contains urea and so urine + water = DEF is 100 percent incorrect and will result in a slew of costly mechanical issues. In either urea or water, the urea contained at urine is neither in the proper concentration for DEF, nor is it of sufficient purity. To summarize, urine and DEF equals Never. REMEMBER NOT TO PEE IN YOUR DEFENSE TANK!

How does a diesel exhaust fluid system work?

Upstream of a catalyst, small amounts of diesel exhaust fluid (DEF) are fed into the exhaust, where it vaporizes and decomposes to generate ammonia and carbon dioxide. The desired result is ammonia (NH3), which, when combined with the SCR catalyst, transforms NOx to harmless nitrogen (N2) and water (H2O).

Can I pee in DEF tank?

A local dealer paid Consumer Reports $317 to add 7.5 gallons of AdBlue in its Mercedes-Benz GL320 test car, with the fluid costing $32/gallon. Most dealers buy AdBlue in bulk (albeit 7.5 gallons in half-gallon bottles would only cost $116.25).

What if the motorist is in the middle of nowhere, miles away from the nearest dealer? Is it possible for him or her to supply some temporary urea in order to get the car to a dealer? The question arises due to the presence of 2 to 4% urea in human urine.

Unfortunately, the answer is “no.” Your pee is not the correct substance for a modern clean diesel automobile to recognize.

Can you run a diesel without DEF?

SCR is quickly becoming one of the most critical components in diesel automobiles. With tougher pollution restrictions and regulations, diesel vehicle owners need make sure their SCR systems are in good working order.

It’s also critical to check that the diesel exhaust fluid level is enough. Without DEF, modern trucks will not run. As a result, diesel truck owners must check their fluid levels on a regular basis. Everyone should strive to reduce pollution. Maintaining your vehicle will also help you save money on emissions and DEF.

Can I use water instead of DEF?

It’s unlikely that removing the urea from the DEF — that is, running water through the injectors instead — will harm the system because the level and quantity of corrosive reactants inside the stainless steel SCR system will be reduced.

Is diesel exhaust fluid made from pig urine?

That’s why, starting in 2010, all diesel trucks were required to have systems dedicated to putting DEF to use. Diesel Exhaust Fluid, which is made up of 32.5 percent urea and 67.5 percent de-ionized water, is sprayed into a vehicle’s exhaust system to aid in the breakdown of NOx emissions, converting them to harmless nitrogen and water. If you’re thinking to yourself, “Urea is a type of urea. You’re on the right brainwave if that sounds oddly like ‘urine.’ When a body metabolizes protein, it produces urea, an organic molecule. (We do, in fact, excrete it as pee.) However, despite DEF’s moniker, “Diesel Exhaust Fluid is really constructed of commercial-grade urea—synthetic ammonia and carbon—and is referred to as “pig urine.”

To put it another way, the urea and water in DEF heat up and produce ammonia. The NOx emissions are subsequently neutralized as the ammonia breaks down. The tail pipe emits fewer harmful substances, allowing everyone to breathe a little better.

What happens if you put diesel in your DEF tank?

To meet EPA pollution rules, most new diesel trucks are fitted with selective catalytic reduction (SCR) systems that utilise diesel exhaust fuel (DEF).

What is a SCR system?

A catalyst reacts with engine exhaust to break down ecologically hazardous exhaust components in the SCR system. Injector nozzles, in a nutshell, spray controlled dosages of DEF into the exhaust. The DEF vaporizes and decomposes into ammonia and carbon dioxide, which mix with the nitrogen oxide in the exhaust to produce the harmless nitrogen and water byproducts.

First of All

DEF fluid is only for vehicles with the SCR system, therefore don’t try to use it on an earlier truck. Although this may seem self-evident, uninformed owners – and even well-intentioned service station attendants and technicians at non-diesel shops – have mistakenly assumed that because DEF is so wonderful for new diesel trucks, it must also be good for older diesel trucks.

Despite the fact that measures have been put in place to keep diesel fuel separate from DEF, it still happens: DEF is placed into the diesel tank by accident, or diesel is poured into the DEF tank by accident. When this happens, it’s more than a little annoyance: it can result in major damage and pricey repairs.

A fill port, a tank, and lines from the tank to the SCR and injection nozzles make up the DEF system. The dispensers should be properly labeled, and the DEF tank’s fill port, which has a blue cap, is designed to be smaller than the diesel tank’s fill port, preventing the diesel nozzle from being inserted into the DEF tank’s fill port.

Non-DEF chemicals are detected by SCR systems, which include built-in warnings. If non-DEF enters the SCR catalyst, the driver will receive a warning and a code indicating approaching SCR interruption.

What Happens If I Put Diesel into a DEF Tank?

Because diesel is lighter than DEF, it will float on top of it. If it gets inside the SCR catalyst, it can cause substantial damage, necessitating service or, worse, a (expensive) catalyst replacement. Before replenishing the DEF tank, it should be drained and thoroughly cleaned with deionized water. A single teaspoon of a foreign contaminant can contaminate a full tanker load of DEF.

What Happens If I Put DEF into a Diesel Tank?

You remove the fuel cap and open the fuel filler door, and your brain goes into automatic mode.

Putting DEF in the diesel tank is a simple error that could result in a truck being towed to the junkyard.

Because DEF is made up of urea and water, the entire tank of fuel becomes contaminated right away. Long-term implications will ensue if the engine is started and the diesel and DEF combination is introduced into the engine.

The DEF fluid crystallizes once the engine is started, causing irreversible damage… and the repair might cost as much as $12,000.

DEF corrodes and damages a variety of metals, including carbon steel, brass, aluminum, copper magnesium-nickel, and zinc.

Can you pour DEF down the drain?

When sprayed into the exhaust stream of diesel automobiles, diesel exhaust fluid (DEF) is a non-hazardous solution that breaks down toxic NOx emissions into nitrogen and water. It is not a fuel additive and does not come into contact with diesel fuel because it is stored in a separate tank. Contractors must understand how to use and store DEF effectively as the use of DEF in Tier 4 Final machines grows.

But what happens if this critical solution “fails?” When faulty DEF is used in a piece of equipment, a variety of problems can arise, including:

Fortunately, knowing the qualities of DEF can assist in keeping it in good working order for equipment. There are seven main areas to consider:

Because DEF has no preservatives, it has a limited shelf life. Thankfully, it lasts a long time — it can normally be kept for up to a year.

DEF must be kept in ISO-certified containers comprised of long-lasting composite materials. Because DEF is corrosive to aluminum, stainless steel, polypropylene, and high-density polyethylene containers are preferred. Because of the risk of fluid contamination, it is not suggested to reuse DEF containers.

DEF and all other fluid storage containers should also be clearly labeled. This can help prevent people from mistaking DEF for conventional fuel or another fluid that could cause catastrophic harm if put in the wrong machine tank.

DEF is unaffected by freezing temperatures. It will start to get slushy at 12 degrees Fahrenheit and eventually freeze solid, although it can be thawed and used without issue. However, because it expands when frozen, it’s recommended not to fill containers to the brim.

While DEF is unaffected by the cold, extended exposure to heat and sunlight might cause the solution to deteriorate. It’s best to keep DEF at 50 degrees Fahrenheit. However, even if it is stored in a cold environment with proper containers, direct sunlight is still harmful to DEF, therefore it should be kept indoors or in the shade.

When dispensing DEF, keeping container nozzles and equipment fill points clean can assist prevent contamination. Only the nozzle of the storage container should be used to discharge it straight into machines. It should not be dispensed through a funnel or moved to another container, even if it is clean, because dirt or other contaminants could contaminate it.

It’s also worth noting that DEF should never be used in a diesel fuel tank of a machine. DEF has its own tank with a smaller aperture and a blue cap that makes it simple to spot.

Despite the fact that DEF is not hazardous, flammable, or explosive, it should be handled with caution to avoid spillage, eye contact, or inadvertent intake.

Cover any spilled liquids on the floor with an absorbent, non-combustible material such as sand. Collect the waste and dispose of it in an appropriate container. If it spills in a sink, on a vehicle or clothing, or gets into your eyes, rinse it out with water right away.

DEF should be stored and used properly by all members of the company’s staff. It is suggested that one person be in charge of DEF care, so that others can learn about best practices.

Do not use DEF if it has gotten polluted or deteriorated. Looking for a hazy or tinted appearance is the easiest method to tell if DEF is polluted or deteriorated. Because DEF is normally clean, any discoloration or cloudiness indicates that it has become contaminated. Contaminants that are visible include small particles, bigger boulders, and dirt.

Bad DEF should be dealt of as soon as possible and in an ethical manner. Pouring it down the drain or dumping it outside is not a good idea. To understand how to properly dispose of DEF, contact your local government and environmental agency.

It’s critical to know how to store and care for DEF appropriately. You can save money on squandered DEF and equipment damage by training your crew on how to save and use DEF.

What year did diesel exhaust fluid start?

When it comes to diesel engines, the agency has tightened rules since 1970. Prior to 2008, no one had to be concerned about the emissions that their equipment or vehicles produced; however, the first step was taken when the EPA mandated the installation of diesel particle filters on all 3/4-ton and bigger trucks. The EPA introduced diesel exhaust fluid (DEF) 2010 with the purpose of further decreasing engine emissions, particularly NOx and particulate matter. NOx and particulate matter were connected to a variety of respiratory and cardiovascular ailments, resulting in thousands of additional hospitalizations and deaths, according to their research.

With DEF being mandated by the EPA, you will find most new diesel trucks, SUVs, cars, and machinery are manufactured with selective catalytic reduction (SCR) technology and a DEF tank that needs to be filled.

When DEF is sprayed into the exhaust stream after combustion, the magic happens, removing the worry of power or torque loss. Once the DEF and hot gases chemically interact, the once-harmful NOx and particulate matter are converted to nitrogen and water, which is then expelled from the exhaust.

While many owners of SCR vehicles have reported greater reliability and longer oil change intervals, it is crucial that the DEF tank does not run dry.

Many engine manufacturers have installed numerous warning lights when the DEF level drops too low – and if it does, the engine’s performance will be reduced to keep the speed limited until the tank is full.

A common assumption is that owners need to fill their DEF with each time they fill their fuel tank, however this is false.

The typical rate of DEF usage is 2.5 gallons per 800 miles travelled, depending on how much you’re hauling. DEF is now accessible at the pump or in jugs inside gas stations, as it has become a requirement in an increasing number of automobiles. It is also strongly advised that you do not attempt to make your own DEF – due to the necessity of having the right mixture to avoid damaging your vehicle’s SCR system.

Instead, purchase DEF in portable containers, at the pump, or in bulk quantities to be kept in a refillable bulk DEF tank at truck stops, retail sites, and fleet oil distributors, depending on your needs.