Subaru 2003 Impreza - Manual (Page 353)

IMPREZA(NA) A1850BE-A (ENGLISH)
Maintenance and service
11-30
1) Upper level 2) Lower level
3. Pull out the dipstick again and check the oil level
on it. If it is below the lower level, add oil to bring the
level up to the upper level.
J Recommended grade and viscosity
Each oil manufacturer has its own base oils and ad-
ditives. Never use different brands together.
Oil grade: API classification GL-5
SAE viscosity No. and Applicable Temperature