Checking the level and replacing the oil in the automatic transmission (BMW 3 Series E21)

Checking the oil level

Place the car on a flat horizontal surface and apply the handbrake. Let the warm engine idle and move the selector lever to the "P" position.

Remove the dipstick and wipe it with a hard, lint-free cloth and check the oil level, which should be between the marks on the dipstick.

Oil change

Replace the gearbox oil every 30,000 km. Do this immediately after the trip, while the oil is warm. Park the car on a flat horizontal surface and tighten the handbrake.

Move the selector lever to position "P". Stop the engine. Unscrew the drain plug, drain the oil and screw this plug back in.

Pour about 1 liter of ATF Oexron II oil into the gearbox and start the engine at idle speed.

Add oil to the gearbox to a level equal to 2/3 of the gap between the lower and upper marks on the dipstick.

(The original article is posted on the resource: BMWMan)