Front Differential Assembly: Adjustment

Using the ST, screw-in the retainer until resistance is felt.
NOTE: RH side should be screwed-in more than LH side.

ST 18658AA020 WRENCH COMPL RETAINER

Fig 1: Tightening Retainer Screw Using ST
Courtesy of SUBARU OF AMERICA, INC.
Remove the remaining liquid gasket from the mating surface completely.
Using the ST, install the drive pinion assembly to converter case.
ST 18270KA020 SOCKET (E20)

NOTE: Do not confuse the three different-length bolts when installing.

Tightening torque:

43 N.m (4.4 kgf-m, 31.7 ft-lb)

Fig 2: Drive Pinion Assembly Bolts Tightening Sequence
Courtesy of SUBARU OF AMERICA, INC.
Rotate the drive pinion shaft ten times or more using ST1 and ST2.
ST1 18667AA010 HOLDER

ST2 499787700 WRENCH

Fig 3: Rotating Drive Pinion Shaft Using ST1 And ST2
Courtesy of SUBARU OF AMERICA, INC.
While rotating the pinion shaft, tighten the retainer LH and loosen the retainer RH until the shaft can't be turned anymore. The backlash is "zero" when the pinion shaft comes to the point where it doesn't rotate.
After the "zero" state is established, loosen the retainer LH by 3 notches and secure it with the lock plate. Retighten the retainer RH until it stops. Rotate the drive pinion 2 or 3 times. Tighten the retainer RH further 1-3/4 notches. This sets the preload. Finally, secure the retainer with its lock plate.

Fig 4: Lock Plate Location
Courtesy of SUBARU OF AMERICA, INC.

NOTE: Turning the retainer by every one tooth changes the backlash approx. 0.05 mm (0.0020 in).

Fig 5: Checking Retainer Tooth Angle
Courtesy of SUBARU OF AMERICA, INC.
Insert the two SUBARU genuine axle shafts into differential case.
Part No. 38415AA070 Axle shaft
Install the ST to the drive pinion retainer, and wrap the drive pinion shaft with cloth and pinch with vise pliers. Using a tie-wrap or a wire, fix the vise pliers to the ST.
Make sure the drive pinion shaft does not move.

ST 18763AA000 COMPRESSOR SHAFT

Fig 6: Installing ST To Drive Pinion Retainer
Courtesy of SUBARU OF AMERICA, INC.
Check the backlash is within specification using ST1, ST2 and ST3.
ST1 498255400 PLATE

ST2 498247100 DIAL GAUGE

ST3 498247001 MAGNET BASE

Backlash:

0.13 - 0.18 mm (0.005 - 0.007 in)

Fig 7: Checking Backlash Using ST1, ST2 And ST3
Courtesy of SUBARU OF AMERICA, INC.
Adjust the teeth contact of the front differential and drive shaft. Ref. to ADJUSTMENT , Drive Pinion Shaft Assembly.