Reduction Drive Gear: Adjustment

WARNING: This page is about a different variant/trim than selected.

Remove the spring retainers and reduction drive gear shims.
Install the transmission case, and secure it with four or five bolts.
Tightening torque:

22 N.m (2.2 kgf-m, 16.2 ft-lb)
Measure depth "A" from the ST upper face to the reduction drive gear end face.
ST 499575400 GAUGE

Fig 1: Measuring Depth From Gauge (499575400) Upper Face To Reduction Drive Gear End Face
Courtesy of SUBARU OF AMERICA, INC.
Raise and hold the reduction drive gear.

Fig 2: Holding Reduction Drive Gear
Courtesy of SUBARU OF AMERICA, INC.
Measure depth "B" from the ST upper face to the reduction drive gear end face.
ST 499575400 GAUGE

Fig 3: Measuring Depth From Gauge (499575400) Upper Face To Reduction Drive Gear End Face
Courtesy of SUBARU OF AMERICA, INC.

Calculate the following formula.

T mm = A - B - 1.0

[T in = A - B - 0.039]

T: Moving distance of reduction drive gear

A: Depth from the ST upper face to the reduction drive gear end surface

B: Depth from the ST upper face to the reduction drive gear end surface

1.0 mm (0.039 in): Thickness of spring retainer

Moving distance of transfer drive gear [T]	Total shim thickness mm (in)
0.420 - 0.519(0.0165 - 0.0204)	0.3 (0.012)
0.520 - 0.619(0.0205 - 0.0242)	0.4 (0.016)
0.620 - 0.719(0.0244 - 0.0283)	0.5 (0.020)
0.720 - 0.819(0.0283 - 0.0322)	0.6 (0.024)
0.820 - 0.919(0.0323 - 0.0362)	0.7 (0.028)
0.920 - 1.019(0.0362 - 0.0401)	0.8 (0.031)
1.020 - 1.119(0.0402 - 0.0441)	0.9 (0.035)
1.120 - 1.219(0.0441 - 0.0480)	1.0 (0.039)
1.220 - 1.319(0.0480 - 0.0519)	1.1 (0.043)
1.320 - 1.419(0.0520 - 0.0559)	1.2 (0.047)
1.420 - 1.519(0.0559 - 0.0598)	1.3 (0.051)
1.520 - 1.619(0.0598 - 0.0637)	1.4 (0.055)
1.620 - 1.719(0.0638 - 0.0677)	1.5 (0.059)
1.720 - 1.819(0.0677 - 0.0716)	1.6 (0.063)
1.820 - 1.920(0.0717 - 0.0756)	1.7 (0.067)

Select one to three reduction drive gear shims so that the total thickness meets the value obtained from step 5.

Part No.	Reduction drive gear shim thickness mm (in)
31288AA260	0.3 (0.012)
31288AA270	0.4 (0.016)
31288AA280	0.5 (0.020)
31288AA290	0.6 (0.024)