Hope this helps - oil capacities for Saturns from a GM document:
Saturn
Year Description Liters Qt
1996-2008 All Models
1996-2002 S Series 1.9 L L4 3.8 4
2000-05 L Series 2.2 L, 3.0 L 4.7 5
2003-07 Ion 2.2 L, 2.4L 4.7 5
2004-07 Ion 2.0 L Supercharged 6 6.3
2002-03 Vue 2.2 L, 3.0 L 4.7 5
2004-08 Vue 2.2 L, 2.4L 4.7 5
2004-07 Vue 3.5 L 4.3 4.5
2008 Vue 3.5 L 3.8 4
2008 Vue 3.6 L 5.2 5.5
2005-07 Relay 3.5 L, 3.9 L 3.8 4
2007-08 Aura 2.4 L 4.7 5
2007-08 Aura 3.5 L 3.8 4
2007-08 Aura 3.6 L 5.2 5.5
2007-08 Sky 2.0 L, 2.4 L 4.7 5
2007-08 Outlook 3.6 L 5.2 5.5
2008 Astra 1.8 L 4.5 4.8