Where is the transmission stick in a 1997 BMW 328i?

If you can't find the Auto transmission dipstick, then your transmission, like mine, is filled with "Lifetime fluid" and theoretically never needs changing.

However, it may need topping up from time to time, due to seal leakage.

This can be done using special AT fluid.

Genuine BMW Lifetime fluid cost an arm and a leg (typical), but there are compatible alternatives such as Castrol Automatic Transmax Z, that will work OK.

There should be a Green plug on the drain plug on the pan of the transmission, under the car, that gives details of the Transmission being a Lifetime oil..

Typically it is a green colour fluid.

To top up the transmission, simply remove the plug, and pump in the oil until it overflows out the hole, using a small hand pump of some sort. They can be bought very cheaply.

Typical symptoms that indicate the transmission is low on oil are: 1. Gear changes are sluggish and delayed; 2. Noises coming from the transmission such as a whining noise.

Good luck.