The Unignorable Urea: Its Absence Affects Truck Power!

The Unignorable Urea Its Absence Affects Truck Power

As many drivers know, since the implementation of the Euro IV emission standards, urea has become an indispensable part of vehicle maintenance costs. Especially during the Euro V and Euro VI stages, the choice of urea has become more stringent. When it comes to adding urea to trucks, the first thing that comes to mind is purifying vehicle exhaust. So, does using inferior urea affect the power of the truck?

Why do trucks need urea?

As mentioned at the beginning of the article, trucks need urea to purify vehicle exhaust, thereby achieving energy-saving and environmental protection. Why did it start with the Euro IV emissions? The mainstream route for upgrading to Euro IV is SCR technology, which stands for Selective Catalytic Reduction technology. This technology requires the addition of automotive urea to meet the Euro IV emission standards.

Selective Catalytic Reduction technology (SCR technology) is when exhaust gas enters the exhaust mixing pipe after coming out of the turbine. A urea metering injection device is installed on the mixing pipe, which injects a urea aqueous solution. Urea generates ammonia gas (NH3) after undergoing hydrolysis and pyrolysis reactions at high temperatures. Nitrogen oxides (NOx) are reduced using ammonia gas (NH3) on the surface of the SCR system catalyst. Nitrogen gas (N2) is emitted, and excess ammonia gas (NH3) is also oxidized to nitrogen gas (N2). This technology is also the mainstream technology route in Europe, and almost all long-distance cargo trucks and large passenger vehicles in Europe adopt this technology.

The Unignorable Urea Its Absence Affects Truck Power

Does high-quality urea improve power?

As mentioned earlier, the main function of urea is to purify vehicle exhaust, so no matter the quality of the urea, it will not help improve power. Moreover, automotive urea solutions are generally made by mixing high-purity urea and ultra-pure water in a certain proportion. If it is an antifreeze urea solution, a certain proportion of methanol needs to be added.

From the composition of urea mentioned above, we can know that urea is mainly composed of high-purity water and high-purity urea. Therefore, no matter the quality of the urea, it will not help improve power. However, although urea does not help improve power, using inferior urea or not using urea for a long time can have a significant impact on the truck.

The Unignorable Urea Its Absence Affects Truck Power

What are the effects of not adding urea?

Obviously, the first impact of not adding urea to a truck is that the exhaust gas does not meet the standards, violating national regulations. When a truck does not use urea, nitrogen oxides (NOx) in the exhaust gas cannot undergo catalytic reduction. Therefore, the resulting exhaust gas will definitely have an impact on the environment.

The second impact is limited torque, leading to a decrease in power. Generally speaking, the diesel engine determines the injection time and injection amount of the urea injection system based on the electronic control unit of the exhaust pipe temperature sensor and the emission sensor. If urea is not used, the vehicle’s electronic control unit will control the engine based on the exhaust pipe temperature or real-time data detected by the emission sensor, forcibly limiting the engine’s operation to minimize exhaust emissions.

The third impact is the possibility of causing nozzle, pipeline, urea pump, and other components to become easily clogged with crystals or damaged by high temperatures. Once repairs are needed, it will cost a lot of manpower and financial resources, making it not worth the loss. In addition, using substandard, low-quality, and cheap urea solutions can cause blockages in the urea solution delivery pipeline, urea filter, and urea nozzle. If there are too many impurities, it may even cause damage to the urea pump.

At the same time, for diesel trucks that meet the Euro VI emission standards, urea quality sensors have been installed according to national regulations. Its function is to detect whether the urea concentration meets the standard. If the Euro VI vehicle uses low-quality, cheap urea with impurities and trace elements, and its concentration does not meet the standard, the urea injection sensor will notify the entire post-treatment system the moment it is added. This will cause the engine to experience limited torque, reduced power, and increased fuel consumption. In addition, the sensor will upload the detected data to the national regulatory platform for real-time monitoring.

The Unignorable Urea Its Absence Affects Truck Power


In summary, not adding urea will seriously affect the vehicle’s power and emissions. Moreover, not using urea or using substandard, low-quality, and cheap urea can cause damage to the urea pump or post-treatment system, resulting in high repair costs. Therefore, vehicle owners should use high-quality automotive urea reasonably. This will make the entire vehicle’s post-treatment system healthier and more stable, and help improve the vehicle’s overall efficiency.