Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Differential Case Assembly
- Install the washer, differential bevel gear and differential bevel pinion in the differential case (RH). Insert the pinion shaft.
- Attach the straight pin in the reverse direction.
- Install the washer and differential bevel gear to differential case (LH). Put the differential case (LH) on the differential case (RH), and assemble the two differential cases.
- Install the hypoid driven gear and secure by tightening the bolt.
Tightening torque:
70 N.m (7.1 kgf-m, 51.6 ft-lb)
- Measurement of backlash (Selection of washer)
- Install the SUBARU genuine axle shaft to differential case.
Part No. 38415AA070 Axle shaft
- Measure the gear backlash using ST1 and ST2, and then insert the ST2 through the access window of differential case.NOTE:
- Measure the backlash by applying a differential bevel pinion tooth between two differential bevel gear teeth.
- When measuring, fix the differential bevel pinion gear in place with a screwdriver covered with waste cloth, or a similar tool.
Standard:
0.13 - 0.18 mm (0.0051 - 0.0071 in)
ST1 498247001 MAGNET BASE
ST2 498247100 DIAL GAUGE
- Install the SUBARU genuine axle shaft to differential case.
- If the backlash is not within specification, select a washer from the table below.
Washer Part No. Thickness mm (in) 803038021 0.95 (0.037) 803038022 1.00 (0.039) 803038023 1.05 (0.041) - Using the ST, install the taper roller bearing.
ST 398487700 DRIFT
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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