Automatic transmission oil filters usually use paper filters, felt filters or membrane filters to remove dirt from their oil. Asian carmakers like to use membrane filters; European and American manufacturers are more inclined to paper or felt filters.

Automatic transmission oil filters are often forgotten when it comes to preventive maintenance. In most cases, transmission oil filters are not as easy to replace as oil filters, air filters or fuel filters. Unless the blockage of the filter has affected the normal work of the transmission, people usually do not replace the filter in time. In fact, since the automatic transmission oil filter is the device that protects the second largest assembly of the car, it should be kept clean or replaced in a timely manner according to its manufacturer's recommended replacement cycle.

During daily maintenance, we need to replace the filter in time to avoid the loss caused by not replacing the filter in time. Some automakers have introduced long-life or maintenance-free transmissions. These transmissions have no dipstick device, and their normal maintenance function flows, and the filter replacement cycle can reach 160,000 km. However, under harsh driving conditions, the conservative maintenance and replacement cycle of the filter should be shortened accordingly, generally 80,000 km.