6 Quarts of oil in the 2.5T
Use only the weight recommended by Volvo and I doubt that they recommend 10w40.
10w30 weight oil.
Use the exact weight your owners manual recommends. Any major brand will work just fine.
5w-30
5w20 weight major brand oil and AC/Delco or Purolator filter would be my advice. I personally use Pennzoil oil. Check your owners manual to be sure on the weight.
86 mm x 16
10w30 is recomended.
5w20
15w-40
use 20W-50 if you don't want it to all leak out.
The proper oil for a 2006 Kia Sedona is 5W20.