How often should the transmission fluid in an automatic transmission car be changed?
2 Answers
For an automatic transmission car, the transmission fluid should generally be replaced every two years or every 40,000 kilometers driven. More information about transmission fluid is as follows: 1. Any type of fluid has an expiration date and needs to be replaced after a certain mileage or period of use. 2. Transmission fluid serves the functions of transmitting hydraulic power and cleaning and lubricating. If the car is used for a long time without changing the transmission fluid, the fluid particles may enlarge or generate debris, blocking the oil passages and potentially causing transmission malfunctions. Therefore, transmission fluid must be replaced regularly. 3. There are two methods for changing transmission fluid: one is the gravity drain method, and the other is the machine flush method.
I've been driving automatic transmission cars for many years, and the frequency of transmission fluid changes really depends on the situation. Based on my experience, it's generally recommended to change it every 40,000 to 80,000 kilometers or every 3 to 5 years, but you must check your owner's manual—requirements vary significantly between different models. For example, I drive a Japanese car, and the manual says to change it at 50,000 kilometers, but since my driving habits lean toward long-distance highway driving, I change it earlier at 40,000 kilometers to avoid dirty fluid affecting smooth gear shifts. If you frequently drive in congested city traffic with constant stop-and-go, the fluid temperature tends to rise, aging it faster, so changing it earlier is safer. The consequences of forgetting to change the fluid can be serious—deteriorated fluid can wear out internal transmission components, potentially leading to costly repairs. I personally check the fluid condition every two years, and if there's any unusual odor or discoloration, I address it immediately—don't wait until problems arise. The maintenance shop mentioned that most car owners overlook this detail, resulting in transmission failure and compromised driving safety.
