Replacement materials:
Transmission oil (ATF), for example:
- Shell ATF Dexron IID-21 -631
- Mobil ATF 220 D-20104
- Total Dexron IID-2129B
For approval of other transmission fluids, please contact your BMW representative.
The oil level can be checked both when cold and at operating temperature. The operating temperature of the oil is approximately +80°C, when cold the oil temperature is equal to the ambient temperature.
With the engine not running, unscrew the expansion tank cap. Wipe the level indicator on the cap with a clean, lint-free cloth.
Insert the level indicator on the lid into the tank and, without tightening the lid, remove it again. The oil level should be located between the marks on the indicator. If necessary, adjust the oil level. The level should be replenished only with automatic transmission oil (ATF) marked Dexron II, approved for use by BMW (the corresponding inscription must be on the packaging). Be sure to add only new fluid, as even the slightest contamination can lead to a malfunction of the hydraulic system.
Start the engine and add oil if necessary until the level is between the marks.
After this, with the engine running, turn the steering wheel several times to the right and left until it stops, which will remove air from the hydraulic drive.
Stop the engine. The oil level in the tank may rise 5 mm above the MAX mark. Check the sealing gasket of the tank cover for porosity and damage.
Close the expansion tank.