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How Much DEF Does a Truck Use?

How Much DEF Does a Truck Use?

Diesel exhaust fluid (DEF) is necessary for large trucks because these types of automobiles emit more harmful gasses because they carry large and heavy freights.

How Much DEF Does a Truck Use? The semi and heavy-duty trucks have an average DEF capacity of 4 to 5 gallons. Your truck will consume 3% to 5% of DEF relative to the amount of diesel fuel used. The 65 gallons of diesel engines can easily consume 2 to 4 gallons of this fluid. In addition, one gallon provides a mileage of 350 miles to 550 miles depending on the storage condition. People use this fluid to reduce combustion, increase engine power, and improve fuel efficiency.

It is compulsory from the government’s side to use them to improve the environment and reduce pollution.

However, the price of DEF is increasing day by day due to the increased costs of urea. Moreover, you should also check its levels to minimize any damage.

What is DEF?

DEF stands for diesel exhaust fluid which is the requirement of the present era to reduce environmental pollution by decreasing the release of harmful gasses.

It is used in the exhaust system of a diesel truck to convert the toxic gasses into less harmful and less toxic ones.

The solution of deionized water and urea is present in your truck’s separate tank. The primary function of this solution is to covert harmful nitrous oxide into the water and less toxic gasses.

Which type of vehicles need DEF?

There are specific types of vehicles that need this solution to decrease the environmental pollution. For example, heavy trucks’ exhaust system has more emissions than smaller ones.

The large and heavy-duty vehicles have larger diesel engines that emit more gasses from the exhaust system.

It is necessary to reduce these gasses to make the environment safe for living and non-living organisms.

Moreover, medium-duty automobiles also need that because of their diesel engines. The heavy-duty trucks are used for carrying large freights, so they have diesel engines.

You must directly inject this liquid into the exhaust system to reduce emissions.

How much DEF is enough for trucks?

The diesel exhaust fluid consumption is relatively lesser than the amount used in diesel. Therefore, you required 2 % to 3% of daily consumption of diesel.

Moreover, you can also adjust the ratio between 60:1. The 60 ratio means that for every 55 to 60 gallons of diesel, you will require 1 to 2 gallons of diesel fluid.

In addition, you can also travel 300 miles to 600 miles with one gallon of DEF and 50 gallons of diesel.

On average, heavy and medium-duty trucks consume approximately 1 to 2 gallons of liquid every 400 to 500 miles.

Things to consider when using DEF in your truck

You have to consider various things while using DEF in diesel engines. The consumption of this liquid depends on the following factors.

Engine efficiency

The DEF consumption in your vehicles depends on the efficiency of diesel engines. The larger engines with more horsepowers will automatically consume more fluid.

More fluid is necessary to reduce the rate of consumption and emissions. Moreover, less efficient engines are also present in vehicles that use more fluid.

In addition, the efficiency also depends on the quality of the engines.

Model of trucks

The DEF use also depends on the type of vehicle and its specific model. Most of the old models are not equipped with efficient and high-quality engines.

These old models will use more gallons of this liquid than the normal range. As a result, it can increase your costs to purchase the new ones again and again.

Climatic conditions

The climatic conditions also affect its consumption due to temperature changes. The average temperature for their storage ranges from 150 to 860 Fahrenheit scale.

The dry and hot climate will increase its consumption due to changes in consistency. The less fluid will consume during cold weather and in the winter season.

It expands and freezes in cold weather when the temperature falls from its normal range.

Types of roads

Driving on uneven and bumpy roads also causes the engines to use more DEF than in normal road conditions.

The engine needs more power to drive on these roads, and the combustion rate of harmful gasses increases, which can cause issues later.

You must reduce these emissions while driving on bumpy roads by consuming more DEF liquid.

How long does a DEF last in a truck?

This fluid is present in large tanks to maintain their storage temperature. It is mentioned with the date of expiry and manufacturing date.

You have to check this 6-digit code before purchasing them from the market. On average, the DEF fluid will last for about 10 months to 12 months.

The longevity depends on its storage temperature and conditions. The average tank lasts from about 6000 miles to 6500 miles.

The average shelf life is about 1 to 2 years with an appropriate storage temperature. You can also increase or decrease this longevity after providing a suitable environment.

How often do you put DEF in a diesel truck?

The truck uses 2 to 3% of DEF relative to the fuel used. So it shows that your truck has an average fuel capacity of 60 to 65 gallons; it can consume 4 to 5 gallons of this liquid.

It shows that you have to replace the liquid every 3 to 5 times when you refill the tank with fuel.

You have to refill the tank when 3 to 4 inches of fluid remain in the tank to avoid any issues.

How do you check levels of DEF in a truck?

The storage tank is on the first side of the diesel tanks of your truck. In addition, in some types of vehicles, it is also present where the spare tire is present.

The new and latest model of automobiles has a warning sign system to represent the low level of DEF liquid in the tank.

You can see that the warning light becomes on when their level is low. This is because the dashboard warning system alerts the drivers when levels are lower than 10% to 15% so that you can refill it.

How do you manage DEF consumption in your truck?

You can conserve DEF consumption by using different methods and reduce the refilling costs several times.

The basic information for management is that you should not store them in bottles or funnels. This is because the fluid contains deionized water, which means that it can evaporate.

Store them in closed containers to reduce the risk of evaporation. In addition, you should also prevent them from the entry of extra water because its levels are set at a specific ratio.

It cannot perform well when you disturb its ratio and add more water. In addition, you also have to prevent the entry of fuel and greases.

Many people use different things to keep it from melting during cold weather, which can cause damage to them.

It is also necessary to store them away from the sunlight. Therefore, you should place their containers indoors and in shady areas.

Why do people use DEF in trucks?

People use this liquid because of its several advantages that can reduce the daily maintenance costs of their trucks.

Reduce combustion

It is necessary to use this fluid in all heavy-duty vehicles because of their greater emissions. The toxic gasses released during driving can make the environment dirty and unsafe for people.

These toxic gasses are not safe for humans and other living objects. So the government made it compulsory to use it to reduce the rate of combustion and environmental pollution.

You inject this fluid into the exhaust system because gasses are released from this system. The urea and deionized water convert these toxic gasses into less harmful forms.

Improve fuel efficiency

It improves your truck’s fuel efficiency by working with an SCR system.

SCR system stands for selective catalytic reduction system that injects liquid into the exhaust to convert harmful nitrous oxide into less toxic gas.

Improving fuel efficiency and mileage is beneficial by decreasing the risk of build-up in the engine compartment.

The engine consumes less fuel when no harmful chemicals or gasses are on its surface.

The engine power reduces, and your truck consumes more gasses when there is the release of more harmful chemicals from the exhaust system.

The engine takes more effort to start due to these deposits.

Reduce maintenance

This advanced system also reduces your automobile’s maintenance and regeneration costs by optimizing the deposits on different parts.

You do not need to change the catalytic converter filter several times because of the build-up of heavy and harmful gasses.

In addition, it can reduce the emission of harmful chemicals, which provides safety to several systems, including exhaust and engine components.

Protect engine

It also reduces the normal wear and tears in the engine compartment by reducing its working efficiency. This is because engines do not have to work harder in the presence of this liquid.

The old models are not equipped with DEF liquid tanks, and their engines consume more power and become faulty due to the accumulation of harmful gasses.

The addition of this fluid increases the performance and efficiency of engines.

How much DEF does a truck hold?

The DEF holding capacity of every truck is different, and it depends on its model and brand name. Moreover, it also depends on the size of the specific vehicle and its weight holding capacity.

On average, the semi, and heavy-duty vehicles have a DEF capacity of 3 to 6 gallons. The weight of every gallon is about 8 pounds to 10 pounds.

Your automobile uses 3% to 4% of this fluid relative to total fuel consumption.

What happens when your truck runs out of DEF?

You must move towards a nearby refilling station when you see a warning light on the screen. It can cause damage to the engine when you ignore this warning sign for a longer time.

Most vehicles have an automatic system to convert them into limp mode or less power usage.

The main function of limp mode is to reduce the ignition times to reduce power supply and emissions.

Moreover, the speed of your vehicle is also reduced due to its low levels. After refilling the tank, you can get out of the engine from limp mode.

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