How do you add transmission fluid on 1998 BMW 328i?

Answer 1

Since you are asking this question I am assuming you have the manual transmission. The fill plug is on the passenger side of the transmission and the drain plug is on the bottom. They are 17mm ( this size may vary ) Allen plugs. Jack the car up but keep it even. This means four jack stands. Remove the fill plug first then, with a catch pan underneath, remove the drain plug. Allow all the fluid to drain out, this may take some time. To speed up the process one might take the car on a little spin first so the fluid heats up and becomes more viscous. Replace the drain plug. Using a hand pump fill the transmission with the correct gear oil until it begins to spill out the fill hole. Wait for the leakage to stop. That is the correct level for the fluid. Replace the fill plug. Make sure you research the proper oil for your transmission; there where three types.