Subaru 2003 Legacy Owner's Manual page 472

GAS STATION REFERENCE
Fuel:
2.5 Liter models:
Use only unleaded gasoline with an octane rating of 87
AKI or higher.
3.0 Liter models:
Use premium unleaded gasoline with an octane rating of
91 AKI or higher. Regular unleaded gasoline with an oc-
tane rating of 87 AKI may be used if necessary. For opti-
mum engine performance and driveability, it is recom-
mended that you use premium grade unleaded gasoline.
Fuel octane rating:
This octane rating is the average of the Research Octane
and Motor Octane numbers and is commonly referred to
as the Anti Knock Index (AKI). Refer to "Fuel" section in
this manual.
Fuel capacity:
16.9 US gal (64 liters, 14.1 Imp gal)
Engine oil:
Use only API classification SL with the words "ENERGY
CONSERVING"
and the New API certification mark (starburst mark) dis-
played on the container.
Engine oil capacity:
2.5 liter models
4.2 US qt (4.0 liters, 3.5 Imp qt)
3.0 liter models
6.1 US qt (5.8 liters, 5.1 Imp qt)
Cold tire pressure:
See the label located under the driver's door latch.