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.
Front Differential: Assembly
When replacing the side bearing, always replace it together with inner race and outer race.Β
- Set the differential bevel pinion, thrust washer and differential bevel gear, and then install the pinion shaft.NOTE:
Apply differential gear oil on the sliding portion of the differential bevel gear, thrust washer and pinion shaft.Β
- Measure the backlash between the differential bevel gear and differential bevel pinion, and select a thrust washer.
- Install the ST to the differential case.NOTE:
The ST is a SUBARU genuine part.Β
Preparation tool:Β
ST: Axle shaft (38415AA070)
- Measure the backlash between the differential bevel gear and differential bevel pinion using the magnet stand and dial gauge (lever type).NOTE:
- Set the dial gauge (lever type) so that its needle contacts the differential bevel gear tooth.Β
- When measuring, fix the differential bevel pinion in place.Β
Specification:Β
0.13 - 0.18 mm (0.005 - 0.007 in)
- If the backlash is outside the standard
- Measure the thrust washer thickness.
- Referring to the measured values of backlash and thrust washer, select the thrust washer.
- Install the ST to the differential case.
- Align the pinion shaft and differential case holes, and install a new spring pin from the driven gear side.
- Using the ST1, ST2 and a press, press-fit the side bearing inner race RH and LH.
Preparation tool:Β
ST1: BUSHING 1-2 INSTALLER (499277100)
ST2: SEAT (398497701)
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
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