What is the difference between gravity transmission fluid change and machine flush?

[AngeloLynn]

The differences between gravity transmission fluid change and machine flush are as follows: 1. The amount of transmission fluid consumed differs: Gravity change can only drain about 70% of the old transmission fluid, while machine flush can remove over 90% of the old fluid. 2. The principles are different: Gravity change involves directly loosening the drain plug at the bottom of the transmission, allowing the fluid inside to drain out by gravity. Machine flush, on the other hand, requires first draining the old fluid by loosening the drain plug, then connecting a flushing machine, starting the vehicle, and adding new fluid into the transmission to push out the old fluid under pressure. 3. The advantages and disadvantages vary: The benefit of gravity change is that the maintenance operation is relatively simple and requires less fluid. However, more old fluid remains in the transmission, mixing with the new fluid and shortening the maintenance cycle. Machine flush consumes more fluid and the operation is more complex, but it prevents the mixing of old and new fluids, which is more beneficial for the transmission's operation.