1. Purchase the correct transmission fluid. The type of fluid you need will vary depending on the model and year of your Astra, so be sure to check your owner's manual or consult with a qualified mechanic.
2. Locate the transmission fill plug. The fill plug is typically located on the side of the transmission, near the top. It is usually marked with a "T" or "Fill" symbol.
3. Remove the fill plug. You can use a wrench or a socket set to loosen the fill plug. Be careful not to drop the plug into the transmission.
4. Insert the fluid transfer pump into the fill hole. The fluid transfer pump is a long, thin tube with a suction cup on one end. Insert the suction cup end into the fill hole and extend the tube to the bottom of the transmission.
5. Begin pumping fluid into the transmission. Slowly pump the fluid into the transmission until it begins to overflow out of the fill hole.
6. Replace the fill plug. Once the transmission is full, replace the fill plug and tighten it securely.
Note: It is important to only add the amount of fluid specified in your owner's manual. Overfilling the transmission can cause damage to the gears and seals.
