All You Need To Know About Adblue Or DEF Diesel Exhaust

adblue-or-def-diesel-exhaust-in-india 14 May 2020

Diesel Exhaust Fluid (known as DEF and also marketed as AUS 32 and AdBlue) happens to be a liquid that is employed to bring about a reduction in air pollution that happens via a diesel engine. To be more specific, DEF comprises an aqueous urea solution with 32.5% urea and 67.5% of deionized water. DEF gets consumed in the process of selective catalytic reduction (SCR) and the process lowers nitrogen dioxide (NO2) concentration in the emissions from a diesel engine or diesel exhaust emissions. 

AdBlue comprises a fluid that is a mix of deionized water and urea and this mixture is squirted into the exhaust system of the vehicle, thereby helping in the reduction of nitrous oxide emissions that are a byproduct of the diesel engines. Car manufacturers of today have to abide by very strict emission targets and in this regard AdBlue is very important, as it ensures that diesel vehicles pass emission tests and spew out less polluted fumes. 

What is the function of AdBlue and why we need it?

There are various rules that govern car manufacturing and these are done keeping environmental concerns in mind. Euro6 is the latest emission regulations and it came into effect in April 2020 in India, representing a serious challenge to the development of diesel engines. A lot of this has to do with the new ways in which nitrogen-oxide emissions can be reduced. 

The technology that is employed is called selective catalytic reduction (SCR) and the process involves the injection of exact amounts of a liquid into the exhaust gases of the vehicle such that a chemical reaction takes place that neutralizes any harmful emissions. 

Working principle of AdBlue

AdBlue gets fed into the exhaust and it produces a reaction with the harmful nitrogen oxide gases that are a byproduct of the combustion process and resultant is that the reaction produces nitrogen and oxygen that are harmless. 

The AdBlue at high temperatures is turned into ammonia and nitrogen oxide is broken down in the process; this means that the total volume of the emitted particles is reduced significantly. This process is also known as Selective Catalytic Reduction which is a system that introduces or injects a solution like AdBlue via a catalyst in the exhaust system of the vehicle. 

What is AdBlue comprised of?

AdBlue happens to be a nontoxic liquid which in appearance is colorless and is basically a solution of urea and water (urea is a substance found in urine). But in AdBlue, the urea present is very pure and of a higher grade than what is used in glue, fertilizers, or cosmetics. Also, the water present is demineralized and is much cleaner than tap water. 

At the time of buying AdBlue you need to check that AdBlue meets the right specifications, therefore look for the ISO 22241 numbering printed on the package. You might also find it appearing as ISO-22241-1, ISO 22241-2, or ISO 22241-3. The numbering ensures that the AdBlue will not damage the SCR catalyst of the car, in the event of which you would be liable to pay for costly repairs to the car. 

Will my car come with AdBlue?

If you are driving a diesel car that is comparatively new, the chances are high that it comes with the AdBlue technology. You will not find it advertised but different manufacturers like BMW, Mercedes, Volkswagen, Jaguar, and Audi have AdBlue incorporated in the system of the car. A lot of manufacturers will furnish a clue in the name, for example, Volkswagen has the initials SCR in the names of some of the cars in its stable. You are advised to look in the handbook to check if the car comes with AdBlue. 

When do I have to top up on AdBlue?

You might be told by your dealer as to when to top up on AdBlue if your car has that technology, a first sign that the AdBlue needs topping up is when you will see a warning sign on the dashboard of you’re your car. 

At a time, only very small amounts of AdBlue are used, hence you do not need topping up as regularly as fuel. However, it is important to note that you should not let the supply of AdBlue run out. 

For example, the Volkswagen Passat will need about 1.5 liters of AdBlue for every 1000 km, if the tank size is 13 liters, a full tank comprising of AdBlue will be sufficient for 12,900 km of driving. 

Also, various driving styles, types of journey, and also the driving conditions will have an impact as to how much of AdBlue is used. 

What do I do if I run out of AdBlue?

To put it very simply, you will find that your car is not starting. It would be careless of you to run out of the supply of AdBlue, this is because the majority of cars will give a warning sign on the dashboard quite far in advance-about 2,500kms before the AdBlue runs out. Also, you cannot put a small quantity of AdBlue in the tank and expect it to work. You will be needing a minimum amount of AdBlue for the car to start again. Our suggestion is that you should tank up on AdBlue as soon as you see the warning sign on the dashboard. You will be saved from a lot of hassles if you do this. Also, practically, you can store a canister of AdBlue in the trunk of your car well in advance so that you will always be prepared.

Where can I top up on AdBlue?

Our website supplies top-up bottles of AdBlue, also you can go to your local dealer for ROWE Motor Oil. You do not need to take your car to the main dealer and get someone to do this process for you, the procedure is similar to topping up with screenwash.

The location of the filter cap is different in cars of different makes, some will have it located right next to the fuel filler cap while the others are on the side of the boot or even underneath the floor of the boot. 

It is essential for you to find out the location of the filter cap well in advance so that you do not have any issues when the time comes for topping up on AdBlue. 

Other things that I need to know about AdBlue

Some experts claim that AdBlue is corrosive in nature and it should be handled with extreme care. Others claim that AdBlue is harmless and if you happen to get it on your hands, all you need to do is wash your hands thoroughly and you’re good to go. If a little amount spills on to the body of the car, just give it a wipedown with a soft piece of cloth. 

Due to these contradictions in opinion, we suggest that you take care of AdBlue much as you would do for the fuel or other liquids. Diesel should not get all over the car, similarly, the oil should not be spilled over the engine. In the same vein, you should take care while refilling with AdBlue. If the reservoir is located in the boot, ensure that you do not fill the wrong tank, especially if it’s a vehicle that has the filler cap right next to the diesel cap. 

The most important consideration in this regard is storage. You will need to store AdBlue in between -11 and 30 degrees centigrade and the fluid has a shelf life of about 12 months when kept in ideal conditions. If you go above 30 degrees C the AdBlue will start to decompose, and below -11 degrees C the AdBlue will begin to freeze. However, it will retain the same qualities after it has thawed. 

As with all things mechanical, you should consult your handbook or give the dealer a call if you are in doubt.

For the best racing engine oil or the best engine oil in India, you should visit The website gives you valuable advice as to what is the best engine oil brand in India and also what is the best engine oil company in India. 

Inquiry Now

Have a question or proposal in mind? Get in touch with us.