33 00... Information on replacing shock absorbers: Facts
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2014 BMW X6, 2013 BMW X6, 2012 BMW X6, 2011 BMW X6, and 2010 BMW X6. However, it is still accessible from the selected car via links, so may be relevant.
When a shock absorber is faulty on one side (leaking, noises, limit values exceeded on the shock tester), often both shock absorbers on the axle in question are replaced.
E32, E34, E38, E39: In the case of rear spring struts with ride-height control, there is always a slight oil spillage on the piston rod. These spring struts are permitted to be wet with oil over a maximum of half the shock absorber length on the outer tube, i.e. they are permitted to "sweat".