How many kilometers should transmission oil be replaced?

[SanRichard]

Generally, transmission oil needs to be replaced every two years or every 40,000 kilometers. Any type of fluid has a shelf life and requires replacement after a certain mileage or period of use. Transmission oil serves to transmit hydraulic power and provide cleaning and lubrication. If a car is used for a long time without changing the transmission oil, the oil particles may enlarge or generate debris, blocking the oil passages and potentially causing transmission failure. If the car is driven on particularly challenging roads or under harsh environmental conditions, the transmission oil may deteriorate over time, necessitating regular replacement. Methods for replacing transmission oil: Gravity Drain Method: Using tools to loosen the nut, the transmission oil will automatically drain out under gravity. Although simple, this method does not completely replace the oil, as residual oil may remain in uneven or hard-to-reach areas. Flush Machine Method: The new transmission oil is stored inside the flush machine, and the machine's pipelines are connected to the transmission's oil passages. Under hydraulic pressure, the new oil pushes out the old oil, resulting in a cleaner oil passage. The more new transmission oil is used, the cleaner the system becomes. A single flush machine oil change typically requires about 10-13 liters of transmission oil and takes approximately one hour to complete.

[OKinsley]

As an experienced driver, let me tell you, transmission fluid is nothing to take lightly. For regular maintenance, I usually change it every 40,000 km for manual transmissions, and every 60,000 to 80,000 km for automatics. This interval also depends on driving conditions – crawling in city traffic every day is different from highway cruising. Last time when I was driving aggressively on mountain roads, I noticed gear shifting becoming rough at just 50,000 km and had to change the fluid immediately. Always use the OEM-specified fluid type – different vehicles require different fluids. Have the mechanic check for any oil pan leaks while they're at it, something many beginners overlook. Transmission repairs can cost tens of thousands, so don't skimp on these few hundred bucks of maintenance.

[SanEverly]

My car has been driven for five years, and the transmission fluid has been changed twice. Nowadays, new car manuals clearly state that automatic transmissions mostly require a change at 60,000 kilometers, while manual transmissions need it a bit earlier. However, in actual use, flexibility is key. Those who frequently haul heavy loads or enjoy flooring the accelerator from a standstill are advised to change the fluid 10,000 kilometers earlier. During the last maintenance, the mechanic used professional equipment to test the fluid quality and mentioned that if there are metal shavings in it, it's time for a change. It's best to replace the filter screen along with the fluid for a complete system refresh. It's recommended to have the workshop check the fluid color during every maintenance service; normally, it should be bright red, and if it turns black or thickens, it's a sign of danger.

[DiTucker]

Based on my experience, don't rigidly follow mileage intervals for transmission fluid changes. For automatic transmissions, changing at 60,000 to 80,000 km is generally fine, but it depends on driving habits. If you frequently drive on mountain roads or carry heavy loads, the fluid may degrade by 40,000-50,000 km. Last time I forgot to change it, which caused gear shift jerking and cost me over 3,000 yuan in repairs. Now I've developed the habit of checking fluid condition every two years. Remember to replace the oil pan gasket when changing the fluid to prevent leaks. After all, transmission repairs are more troublesome than engine repairs, so proper maintenance is the real money-saver.