Gear oil - when to change and how to choose the right oil for manual transmission and automatic transmission?

The role of oil in the gearbox

Cars use various working fluids, including oils. The most common is engine oil, the regular replacement of which ensures trouble-free operation of the car. Too little or too much oil can cause engine seizing and accelerated component wear. 

Is it the same with gear oil? Not necessary. The oil in the gearbox performs several functions, such as:

• lubrication of individual elements;
• reduced friction;
• cooling of hot components;
• softening and damping gear shocks in this part of the car;
• reduced vibration;
• protection of metal parts from corrosion. 

In addition, the transmission oil must keep the inside of the transmission clean. The gear oil must match your vehicle's specification. It is important whether it will be an urban car, whether it will be a sports car or a delivery van. 

Is it worth changing the gearbox oil? Is it really necessary?

In most cases, car manufacturers do not provide for changing the oil in automatic transmissions. So what is the purpose of this? Is it really necessary to change the gearbox oil? Mechanics agree that fresh gear oil lubricates and cools better. It is important that all transmission parts work properly. In many cases, this can help prevent possible failures or even increase vehicle uptime.

Manual transmission oil may not be as stressed as engine oil, but it is just as susceptible to aging. Fresh oil will work better. The gearbox will get longer life because its internal components will be well lubricated and cooled.

You may be wondering why manufacturers don't recommend changing gearbox oil. Perhaps they assume that the new car will stay with the first owner no longer than the expected first change of this fluid in the transmission.

When to change the gearbox oil?

The legitimacy of changing gear oil is undeniable. Find out how often such a replacement is really necessary. Because the oil coats the internal components of the transmission that are in constant motion, transmission life decreases over time. Oil change to the gearbox is recommended every 60-120 thousand. mileage. Some gearboxes equipped with two clutches (double clutch) may require more frequent relubrication than others due to the nature of their operation. It can even be once every 40-50 thousand. mileage.

It would be wise to change the gear oil only after the warranty period has expired. Otherwise, do-it-yourself replacement of the lubricant in the gearbox will void the manufacturer's warranty.

Which oil to choose for manual transmission and which for automatic transmission?

If you decide to replace the tool in the transmission, you need to choose the right working fluid. Manual transmission oil is different from automatic transmission oil because they work a little differently.

The selected oil must meet the specifications of the vehicle manufacturer. Agents are classified according to the API GL scale developed by the American Petroleum Institute. Oils for manual transmissions are in the range 2, 3, 4 and 5. Also important is the viscosity grade, marked with the SAE symbol along with the numbers: 70, 75, 80, 85, 90, 110, 140, 190 and 250.

The oil for automatic transmissions equipped with a torque converter and control clutches or in vehicles with dual clutch must be of a different type - ATF (Automatic Transmission Fluid). It will have appropriate parameters related to its viscosity. Careful selection of transmission oil is critical to the proper operation of the entire transmission. If you choose the wrong product, it may not respond adequately to the materials used by the manufacturer to make the box. Information on which oil to choose is best found in the car's owner's manual.