1998-2001 4-speed AT
Dextron III - Texaco Texamatic 7045 - mineral oil based

Change at:
60,000 miles / 96,000 km (North America)
66,000 miles / 110,000 km (Europe, rest of world)

2002-2009 5-speed AT
Saab 3309 - mineral oil based
Mobil 3309 and Toyota T-IV are often used.

Change at:
60.000 (MY06+), 90,000 (MY05) or 100,000 (MY03) miles

Note: Saab changed the change interval through the years. While they advice 100K miles for MY03, it's safe to assume 60,000 miles should be used for all model years MY02 and up.