根据国家工程机械系列产品装配验收技术条件的要求，装载机、推土机等产品在总装试车后，应将各系统中的液压油、柴油及液力传动油排放干净，并清洗油箱、滤芯或滤网（即通常所谓的“清三箱”），再重新加入符合国家标准的清洁油料，以保证产品的正常使用，提高产品的可靠性。 According to the requirements of assembly and receiving technical conditions of national engineering machinery series products, the loaders, bulldozers and other products should be drained clean of hydraulic oil, diesel oil and hydraulic transmission oil and cleaned of oil tank, filter or filter net (Usually the so-called “clear box”), then re-join in line with national standards of clean oil, in order to ensure the normal use of the product, improve product reliability.