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Engine Lubrication System (2.5L): General Description: Specification

Lubrication method Forced lubrication
Oil pump Pump type Trochoid type
Number of teeth Inner rotor 9
Outer rotor 10
Outer rotor diameter x Thickness mm (in) 78 x 11 (3.07 x 0.43)
Tip clearance between inner and outer rotors mm (in) Standard 0.04 - 0.14 (0.0016 - 0.0055)
Case clearance between outer rotor and pump case mm (in) Standard 0.10 - 0.175 (0.0039 - 0.0069)
Side clearance between inner rotor and pump case mm (in) Standard 0.02 - 0.07 (0.0008 - 0.0028)
Relief valve spring Free length mm (in) 73.7 (2.902)
Installed length mm (in) 54.7 (2.154)
Load when installed N (kgf, lbf) 93.1 (9.49, 20.93)
Performance (Oil temperature 80°C (176°F)) 600 r/min Discharge pressure kPa (kg/cm2 , psi) 98 (1.0, 14)
Discharge rate L (US qt, Imp qt)/min 6.4 (6.8, 5.6) or more
6, 000 r/min Discharge pressure kPa (kg/cm2 , psi) 392 (4.0, 56.8)
Discharge rate L (US qt, Imp qt)/min 63.0 (66.6, 55.4) or more
Relief valve working pressure kPa (kg/cm2 , psi) 538 (5.5, 78)
Oil filter Filter type Full-flow filter type
Filtration area cm2 (sq in) Outer diameter: 68 mm (2.68 in) (black) 800 (124)
Outer diameter: 67.4 mm (2.65 in) (blue) 555 (86)
By-pass valve opening pressure kPa (kg/cm2 , psi) 160 (1.63, 23.2)
Outer diameter x Width mm (in) Outer diameter: 68 mm (2.68 in) (black) 68 x 65 (2.68 x 2.56)
Outer diameter: 67.4 mm (2.65 in) (blue) 67.4 x 65.3 (2.65 x 2.57)
Installation screw specifications M 20 x 1.5
Oil pressure switch Type Immersed contact point type 7
Operating voltage - power consumption 12 V - 3.4 W or less
Warning light operating pressure kPa (kg/cm2 , psi) 14.7 (0.15, 2.1)
Proof pressure kPa (kg/cm2 , psi) 981 (10, 142) or more
Engine oil Total capacity (at overhaul) L (US qt, Imp qt) 5.0 (5.3, 4.4)
When replacing engine oil and oil filter L (US qt, Imp qt) 4.3 (4.5, 3.8)
When replacing engine oil only L (US qt, Imp qt) 4.0 (4.2, 3.5)

Specified oil: 

CAUTION:
  • Use 5W-30 (synthetic oil).
  • It is acceptable to fill an engine with oil of another brand when replacing the oil, but make sure to use the following engine oil specified by Subaru.
Engine oil standard SAE viscosity No.
G10264615G13640836Courtesy of SUBARU OF AMERICA, INC.SUBARU OF AMERICA, INC.

Those with SN or SN PLUS "Resource Conserving" logo in case of API standard.
or
G10264615G13640836Courtesy of SUBARU OF AMERICA, INC.SUBARU OF AMERICA, INC.

Those with GF-5 "starburst mark" displayed on top of the container in case of ILSAC standard.
5W-30 (synthetic oil)
NOTE: The proper viscosity oil helps the engine maintain its ideal temperature, and cranking speed increased by reducing viscosity friction in hot condition.