Checking the function of the clutch
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.
Test drive the car.
If 1st or reverse gear is stiff, but the other gears operate normally or are less stiff, the clutch is slipping. This is caused by excessive friction between the input shaft and the clutch hub.
NOTE:
Moderate tightening of the clutch plates may mean that greater force is required to engage gears, in particular 1st and reverse gears.