Front Differential Assembly: Adjustment

Using the ST, screw-in the differential side retainer until light contact is felt.
ST 18630AA010 WRENCH COMPL RETAINER
NOTE:
- Screw-in the RH side slightly deeper than the LH side.
- WRENCH ASSY (499787000) can also be used.
  
  Fig 1: Identifying Wrench Assy (499787000)
  Courtesy of SUBARU OF AMERICA, INC.
Remove the oil pump housing.
Remove the liquid gasket from the mating surface completely.
Install the oil pump housing assembly to the converter case, and secure them by tightening the four bolts evenly.
NOTE: Use an old gasket or aluminum washer to prevent damaging the mating surface of the housing.

Tightening torque:

41 N.m (4.2 kgf-m, 30.2 ft-lb)

Fig 2: Identifying Oil Pump Housing Assembly
Courtesy of SUBARU OF AMERICA, INC.
Rotate the drive pinion a few times using ST1 and ST2.
ST1 498937110 HOLDER

ST2 499787700 WRENCH

Fig 3: Rotating Drive Pinion Using ST1 And ST2
Courtesy of SUBARU OF AMERICA, INC.
Tighten the differential side retainer LH until contact is felt while rotating the shaft. Then loosen the differential side retainer RH. Keep tightening the differential side retainer LH, and loosening the retainer RH until the pinion shaft no longer turns. This is the "zero" state.

Fig 4: Identifying Differential Side Retainer
Courtesy of SUBARU OF AMERICA, INC.
After the "zero" state is established, back off the differential side retainer LH 3 notches and secure it with the lock plate. Then back off the differential side retainer RH and retighten until it stops. Rotate the drive pinion 2 or 3 times. Tighten the differential side retainer RH 1-3/4 notches further. This sets the preload. Finally, secure the differential side retainer with the lock plate.

Fig 5: Identifying Lock Plate
Courtesy of SUBARU OF AMERICA, INC.

NOTE: Turning the differential side retainer by one notch changes the backlash about 0.05 mm (0.0020 in).

Fig 6: Identifying Differential Side Retainer Turning Position
Courtesy of SUBARU OF AMERICA, INC.
Turn the drive pinion a few times with ST1 and check to see if the backlash is within the specified value, using ST2, ST3, ST4 and ST5.
ST1 499787700 WRENCH

ST2 498247001 MAGNET BASE

ST3 498247100 DIAL GAUGE

ST4 499787500 ADAPTER

ST5 498255400 PLATE

Backlash:

0.13 - 0.18 mm (0.0051 - 0.0071 in)

Fig 7: Turning Drive Pinion Using STS
Courtesy of SUBARU OF AMERICA, INC.
Adjust the teeth contact of the front differential and drive shaft. < Ref. to ADJUSTMENT , Drive Pinion Shaft Assembly.>