When to change the oil in a manual transmission?

Regulation and its observance

The intervals recommended by the automaker for changing transmission oil in all units (not just manual transmissions) are usually prescribed in the "Maintenance" or "Transmission" section of the operating instructions. The key word here is "recommended". Because each car is operated in different conditions. And the rate of oil aging, the intensity of wear of the gearbox parts, as well as the initial quality of the transmission lubricant are individual factors in each individual case.

Should I change the oil in a manual transmission according to the instructions of the car manufacturer or are there any other standards? In the event that the following conditions are met, a scheduled replacement is sufficient.

1. The vehicle is operated under normal conditions. This concept means a mixed driving cycle (approximately the same mileage on the highway and the city) without intense and prolonged overloads, such as driving at close to maximum speed or systematic towing of loaded trailers.
2. No leakage through the pan gasket (if any), axle shaft seals (cardan flange) or input shaft.
3. Normal operation of the gearbox, easy shifting of the lever, no hum or other extraneous noise.

If all three conditions are met, then the oil must be changed according to the manufacturer's instructions. Change intervals usually range from 120 to 250 thousand kilometers, depending on the car model and the oil used. In some manual transmissions, oil is filled for the entire service life.

Cases when the oil should be changed regardless of mileage

There are practically no ideal operating conditions for a car. There are always some deviations from the norms prescribed by the manufacturer. For example, a long trip at maximum speed due to haste, or an extended towing of another, often heavy car. All this affects the life of the transmission oil.

Consider several common situations and characteristic signs in which it is necessary to replace the gear oil in a manual gearbox ahead of schedule, before the scheduled mileage.

1. Buying a used car with good mileage. If you don’t know the previous owner well and there is a possibility that he didn’t change the oil on time, we drain the working from the manual transmission and fill in fresh grease. The procedure is relatively inexpensive, but it will allow you to be sure that the box has been serviced.
2. Leaks through seals. Constant topping up of oil in this case is not the best option. Ideally the seals will need to be replaced. But if this is not possible, change the oil no later than the regulations require. Better yet, more often. Leakage through the seals usually does not mean washing out the wear products from the box. And if we limit ourselves to one topping up, fine chips and heavy oily fractions, oxide products, which later develop into sludge deposits, will accumulate in the box. Also pay special attention to the condition of the lubricant after driving through deep puddles and in wet weather. There are cases when, after such a ride, water seeped into the box through the same leaky seals. And riding on water-enriched lubricant will lead to corrosion of manual transmission parts and accelerated wear of gears and bearings.

3. Hard shifting lever. A common cause is the aging of the lubricant. This phenomenon is often observed on domestic cars closer to the replacement date. Has the lever become more stubborn? Do not rush to sound the alarm. Just change the oil first. In more than half of the cases, after updating the transmission lubricant, the problem of a tight lever either goes away altogether or is partially leveled.
4. Filled with cheaper and lower quality oil. Here also reduce the runs between replacements by 30-50%.
5. The vehicle is driven in dusty conditions or at extreme temperatures. Under such conditions, the service life of the oil is reduced. Therefore, it is desirable to change it 2 times more often.
6. Any box repair with oil drain. Saving on oil in this case is irrational. In addition, you will save yourself for a long time from the need for a separate replacement.

Otherwise, stick to the deadlines.

Do I need to change the oil in the manual transmission. Just about complicated