Forklift gearboxes can be divided into two types. One is a normal manual gearbox. This gearbox has a gear structure with fewer gears, so gear oil is sufficient. However, forklifts usually have a heavy load during work, so GL-5 heavy-duty gear oil should be used instead of ordinary gear oil. This gear oil has a long replacement cycle, usually more than 1,000 hours. Some forklifts never change the gearbox oil, and it is not a big problem to use.

Another type of hydraulic-mechanical gearbox for forklifts is actually a simple two-speed automatic gearbox inside. The power of the engine is transmitted to the gearbox through a torque converter, and the gearbox is controlled by hydraulic pressure. . This gearbox usually uses No. 6 or No. 8 hydraulic transmission oil. The replacement cycle of this transmission oil is shorter, usually 500 hours, it is better to clean the transmission oil pan and replace the transmission oil filter at the same time.

The differential of the forklift is combined with the main reducer and installed in the drive axle. The oil it uses is determined by the type of final drive. If the main reducer is an ordinary conical Gleason or Oerlikon gear, use ordinary GL-5 heavy-duty gear oil; if the main reducer is a hyperbolic gear, then you must use hyperbolic gear oil , Do not use other gear oil instead. The oil replacement cycle here is also relatively long, usually at the same time as the gear transmission oil.

The several oils mentioned above are selected and used according to different forklift types. For the specific type, you still have to look at the regulations in the maintenance manual. If there is no maintenance manual, there is an empirical method: if it is an automatic gearbox, you should replace the No. 8 hydraulic transmission oil; if it is a manual gearbox, use GL-5 heavy-duty gear oil; whichever is the differential Both types use hyperbolic gear oil. Although it is not very economical to use in this way, it will definitely not make mistakes and will not cause damage to the car.