Yes, it is necessary to drain the oil when removing an automatic transmission.
Reasons:
* Protection of automatic transmission components: The oil in the automatic transmission lubricates and cools its components. When removing the automatic transmission, oil leaks out of the housing, leaving the components unprotected, which can lead to damage.
* Ease of operation: Drained oil makes it easier to remove and install the automatic transmission, eliminating interference and reducing the risk of oil splashing.
* Checking the oil condition: When draining the oil, you can check its condition. If the oil contains metal particles, debris, or has a dark color or a burning smell, this may indicate problems with the automatic transmission.
* New Gaskets and Seals: When reinstalling an automatic transmission, new gaskets and seals are usually required to prevent oil leaks. Before installation, make sure that all oil is drained.
Oil drain procedure:
1. Place the car on a level surface.
2. Find the automatic transmission drain plug (usually it is located in the lower part of the housing).
3. Place a container under the plug to collect the oil.
4. Unscrew the drain plug and allow the oil to drain completely.
5. Screw the drain plug back.
6. Check the oil level in the automatic transmission after installing it.