Filling the hydraulic system / air pressure from the hydraulic system of the power steering gear (BMW 5 Series E39)

Bleeding air from the hydraulic system is necessary if the system pipelines have been opened. Refill the system only with new oil, since even minor contamination can disable it.

Oil specification: Automatic transmission fluid (ATF) with the designation Dexron II D, for example:

• Shall ATF Dexron II D-21-631;
• Mobil ATF 220 D-20104;
• Total Dexron II D-21298.

Please contact your BMW dealer for information on the possibility of using other ATFs.

With the engine not running, unscrew the cap of the expansion tank.

Start the engine and let it idle. Immediately top up the oil level to the lower mark MIN "2".

Caution: Operation of the power steering pump without oil is not permitted.

Slowly turn the steering wheel fully left and right twice.

Top up the oil level in the expansion tank again.

Stop the engine and check the oil level.

Top up the oil level to the MAX "1" mark. When topping up the level, add oil in small portions. System filling volume: 1.2 l.

Tighten the cap of the expansion tank.

When the oil is cold (+20°C), its level in the tank should be between the MIN and MAX marks.