How many liters of oil is needed for an oil change in an automobile gearbox is determined according to the way of oil change and the frequency of use of the automobile, and it needs to be determined by specific analysis of specific problems. First of all, let's talk about when it is necessary to change the transmission oil. After all, it is not good to change the transmission oil too often or for too long. In general, the on-board operation and maintenance manual of the vehicle will indicate the replacement frequency of the transmission oil of the vehicle, whether it is time regulation or mileage regulation, as long as the vehicle reaches any node. Of course, if you feel abnormal gear shifting and speed change during driving, you can also replace it.