How much urea consumption per 100 kilometers is normal?
4 Answers
Urea consumption is calculated at 5%~7% of fuel consumption. For example, a heavy-duty truck with 20L/100km fuel consumption will consume approximately 1L of urea per 100 kilometers. In traffic congestion, urea consumption may be slightly lower. Below is more information about automotive urea: Definition: Automotive urea, also known as diesel exhaust fluid (DEF), is a liquid used in SCR (Selective Catalytic Reduction) technology to reduce nitrogen oxide (NOx) emissions from diesel vehicles. Its composition consists of 32.5% high-purity urea and 67.5% deionized water. Reason for adding urea to diesel engines: During operation, diesel engines emit harmful nitrogen oxide compounds that damage both the atmosphere and human health. Prolonged exposure to these gases can cause respiratory diseases. To mitigate these hazards, when urea encounters nitrogen oxides emitted by diesel engines, a chemical reaction occurs, converting the nitrogen oxides into harmless nitrogen gas and water vapor for emission.
I've been driving heavy trucks for long-distance haulage for eight years, and I know all about the urea consumption. For standard-load tractors running on flat terrain, burning 3-5 liters per 100 kilometers is normal. When climbing mountains in Yunnan, Guizhou, or Sichuan, it can shoot up to 6-8 liters, and I've even seen 10 liters when rushing to deliver fresh produce. New China VI engines consume more urea than China V ones because the aftertreatment system is more sensitive. Consumption is lower in winter and higher in summer, and don’t fill the tank too full to avoid crystallization. The key is to check if the exhaust pipe emits white smoke—if it burns clean, you're good. Don’t let repair shops trick you into changing the nozzle; first, check if the urea level warning light is on. My Auman has run 500,000 kilometers, and its urea usage has been very stable.
Just asked a technician friend at the 4S dealership, it's common for diesel SUVs to consume 1.5 to 2.5 liters per 100 kilometers. My diesel H9 measured 2.2 liters in actual testing, and a 10-liter barrel of urea can last about 450 kilometers. Make sure the urea concentration is within the standard range of 32.5%±0.7%, as poor-quality urea can easily clog the DPF. When the dashboard indicates low urea, there are still at least 3-4 liters remaining. For commuter cars, checking the fluid level monthly is sufficient. Once, using cheap urea caused engine torque limitation, and the repair cost nearly two thousand yuan. Now, I only trust genuine products with the CGT mark. In northern winters, remember that urea freezes below -11°C.
Truck drivers often discuss this in group chats. Actual consumption is directly linked to engine displacement: 4-cylinder light trucks consume about 1-3L/100km, 6-cylinder medium trucks 3-5L, and 8-cylinder heavy trucks 5-8L. I drive a Dongfeng Tianlong KX on the Guangzhou route, using cruise control on the highway, averaging around 5.8L/100km per trip. Long idling with AC on can spike consumption abnormally—once, an 8-hour traffic jam burned an extra half tank. Upgrading to a larger urea tank isn’t cost-effective; the key is regular cleaning of the urea pump filter.
