AdBlue® FAQ – Everything You Need to Know
AdBlue® is essential for many modern diesel engines, helping businesses stay compliant with emissions legislation and keeping their fleets running efficiently. Below you’ll find the answers to the most common questions that our customers ask us about AdBlue®, its use, storage and delivery options.
Need to order AdBlue®? Call 0330 123 1444 or fill in our quick quote form and a member of our team will be in touch soon!
What is AdBlue®?
AdBlue® is the registered trademark name for an Aqueous Urea Solution (AUS 32) or Diesel Exhaust Fluid (DEF). It’s a non-toxic, odourless and colourless liquid consisting of 32.5% high-purity urea and 67.5% deionised water. It is not a fuel additive, but a separate fluid used in the exhaust stage of diesel engine systems.
Why do modern diesel engines require AdBlue®?
AdBlue® is required for modern diesel vehicles (typically those manufactured since around 2006, especially commercial vehicles over 7.5 tonnes) that use Selective Catalytic Reduction (SCR) technology. It is essential for meeting strict Euro 4, 5 and 6 emission standards by reducing harmful emissions.
Is AdBlue® harmful?
AdBlue® is non-toxic and safe to handle with basic precautions. Avoid contact with skin or eyes, as it may cause mild irritation. You must ensure you clean any spills immediately to prevent crystallisation or corrosion on surfaces.
Which vehicles use AdBlue®?
Most modern diesel vehicles with Euro 5 and Euro 6 engines use AdBlue®, including:
- Many modern diesel cars
- HGVs and LGVs
- Buses and coaches
- Vans and commercial vehicles
- Agricultural machinery
- Construction equipment
If your vehicle has an SCR system, it will require AdBlue®.
How does AdBlue® work?
AdBlue® is sprayed into the exhaust fumes soon after combustion. In the SCR catalytic converter, the urea converts to ammonia, which then reacts with harmful mono-nitrogen oxides (NOx) in the exhaust. This chemical process breaks them down into harmless nitrogen gas (N2) and water vapour (H2O), which are then safely expelled from the exhaust pipe.
What happens if I run out of AdBlue®?
Your vehicle will give you several dashboard warnings before the tank is empty. If you ignore them:
- Power will usually be reduced
- The vehicle may refuse to restart once turned off
To avoid downtime, keep your tank topped up or arrange regular AdBlue® deliveries through Crown Oil.
Does AdBlue® improve fuel efficiency?
While AdBlue® itself doesn’t improve fuel economy, SCR technology allows engines to be designed for improved performance whilst maintaining emission standards.
How much AdBlue® will my vehicle use?
Consumption varies greatly based on the vehicle type, size, engine and driving style.
Passenger cars: A general rule of thumb is approximately 1 litre of AdBlue® every 600 miles (though it can vary from 350 to over 1,000 miles).
Commercial vehicles/HGVs: Consumption is typically around 5% of the rate of diesel fuel usage.
What quantities of AdBlue® does Crown Oil supply?
Crown Oil supplies AdBlue® in a range of volumes to suit all commercial applications:
- Small packs (e.g. 5-litre, 10-litre, 210-litre barrels)
- 1,000-litre Intermediate Bulk Containers (IBCs)
- Bulk deliveries via tankers up to 25,000 litres for maximum cost-effectiveness
We also supply tanks, dispensing equipment, spill kits and other accessories to help you use your AdBlue® safely.
Does Crown Oil’s AdBlue® meet the required quality standards?
Yes. All AdBlue® supplied by Crown Oil meets the stringent international quality standard ISO 22241 and has VDA quality approval, ensuring it protects your SCR system.
Can I mix AdBlue® from different suppliers?
As long as the product meets ISO 22241 and is branded correctly, it can be mixed. However, contaminated or low-quality AdBlue® can damage your SCR system. Crown Oil only supplies certified, high-purity AdBlue®.
How quickly can Crown Oil deliver AdBlue®?
We offer fast, nationwide delivery, depending on your location and order size. Bulk deliveries can be scheduled as needed, and emergency options are available.
How should AdBlue® be stored?
AdBlue® must be stored correctly to maintain its quality:
- Shelf life: When stored under ideal conditions, AdBlue® has a shelf life of around 12 months before it begins to degrade
- Temperature: Store in a cool, well-ventilated area, ideally between -11°C and 30°C
- Containers: It should be kept out of direct sunlight in a specialised, sealed AdBlue® container or tank
Can AdBlue® freeze?
Yes. AdBlue® freezes at -11°C, but this won’t damage its quality. Vehicles with SCR systems have built-in heaters to defrost AdBlue® automatically.
Do you offer AdBlue® storage and dispensing solutions?
Yes – Crown Oil can supply:
- AdBlue® bunded tanks
- Hand pumps and electric pumps
- Gravity-fed kits
- IBC cages and dispensing equipment
Our team can help you select the right setup for your usage levels – call us today on 0330 123 1444 to find out more.
Do you need to order AdBlue® for your fleet or require advice on the best storage solution for your business? Call Crown Oil today on 0330 123 1444 to speak to one of our specialists.
