Changed oil and filter in my 2005 sts v8. Manual calls for 8 quarts with oil and filter change. Oil seems to be over full mark, even after driving. Is manual correct at 8 quarts or wrong--anybody?

I am pretty sure it is SIX quarts, not eight ...

I am pretty sure it is SIX quarts, not eight ...
The V8 requires 8 quarts.

From the specifications sticky:

Capacities
EPA total volume
(cu ft): 116.7
EPA trunk volume (cu ft): 13.8
Trailer towing maximum (lb / kg): 1000 / 454
Fuel tank (gal / L): 17.5 / 66.2
Engine oil (qt / L): V-6: 5 / 4.7;
V-8: 10 / 9.4

Based on premise engines for V8 STS same as V8 SRX:
(Sorry, I do not believe the 10 qt capacity above for N*V8)
Ref: 2005 SRX Service Manual, pp6-506 - 4.6L (LH2)/&/ pp6-20 - 3.6L (LY7)
**Oil Capacity - with new Dry Oil Filter = 8.0 Qts /&/ = 6 Qts
**Oil Capacity - without Oil Filter Change = 7.5 Qts /&/ = 5.5 Qts
hope this helps

8 sounds right to me too. 10 seems like the oil capacity for a BMW or Merc.