Checking the viscous coupling housing and viscous coupling
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2006 Volvo S80, 2005 Volvo S80, 2004 Volvo S80, 2003 Volvo S80, and 2002 Volvo S80. However, it is still accessible from the selected car via links, so may be relevant.
Check the bearing for play and noise.
Check the viscous coupling mating surface with the pinion seal.
To replace the viscous coupling or bearing, see Bearing viscous coupling, replacing .