LHM hydraulic fluid
WARNING: This page does not describe the selected car, but rather 104 other vehicles, including the 2010 BMW Z4, 2010 BMW X6 M, 2010 BMW X6, 2010 BMW X5 M, and 2010 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.
LHM hydraulic fluid has a favorable viscosity range and permits problem-free operation of the self-leveling rear suspension at very low and very high temperatures. The solidification point is -78°F/-61°C.