我国汽车发动机一般按里程更换机油。但因发动机的技术状态各异,汽车的运行条件千差万别,同样的机油在同样的时间或里程内,其劣化程度不可能一样。有些车没有行驶到换油里程时,机油已严重变质,可仍在继续使用。——造成机件早期磨损;有些车虽已到了换油里程,但机油仍保持良好的润滑性能,却被过早地换掉了,——造成油料浪费。采用常规化验油样的方法,视情更换机油则比较合理。但由于 China’s car engines generally change the oil according to mileage. However, due to the different technical conditions of the engine, the operating conditions of the vehicle vary greatly, and the same oil can not be degraded in the same time or mileage. Some cars did not drive to the oil mileage, the oil has been severely deteriorated, you can still continue to use. - Early wear and tear caused by mechanical parts; Although some cars have reached the oil change mileage, but the oil still maintain good lubricating properties, but was prematurely replaced, - resulting in oil waste. The method of routine test oil samples, depending on the situation to replace the oil is more reasonable. But thanks