Checking Fluid Level
WARNING: This page is about a different car, the 1986 Volvo 760, 1986 Volvo 740, 1986 Volvo 245, 1986 Volvo 244, and 1986 Volvo 240. However, it is still accessible from the selected car via links, so may be relevant.
Fluid should be up to bottom of fill hole. When adding oil, allow sufficient time for oil to flow into overdrive unit.