Changing the oil in the front axle gearbox (BMW X5 E53)

The oil in the front axle gearbox must be changed in the following order. Warm up the front axle gearbox to operating temperature by driving 7-10 km at high speed and set the car horizontally.

• Unscrew the plug (1, Fig. 2.48) filler holes from the front axle gearbox.
• Unscrew the drain plug (M22x1.5) and allow the oil to drain from the front axle gearbox.
• Replace the sealing rings of the threaded plugs of the front axle gearbox. Clean and screw in the drain plug, tightening it to a torque of 65 Nm (6.5 kgf·m). Dispose of the drained oil.
• Pour oil into the front axle gearbox up to the lower edge of the filler hole, until it starts to overflow. Allow excess oil to drain and clean the front axle gearbox housing.
• Screw in and tighten the threaded plug (1) of the transfer case filler hole to a torque of 65 Nm (6.5 kgf·m). Take a short trip, about 5-7 km, and check the transfer case for leaks; oil leaks are not allowed.