WARNING: This page is about a different car, the 2011 BMW 750xi, 2011 BMW 750Lxi, 2010 BMW 750xi, and 2010 BMW 750Lxi. However, it is still accessible from the selected car via links, so may be relevant.
TIGHTENING TORQUE SPECIFICATIONS - FAN
Type
Thread
Tightening specification
Measure
1AZ Fan clutch on water pump Coupling nut (left-hand threads)