2020 Subaru Forester BaseFACTORY OEM SERVICE PROCEDURE

Differential Case

  1. Install the differential bevel gear and differential bevel pinion together with the washer, and install the pinion shaft.
    NOTE: Apply differential gear oil on the sliding portion of the washer, differential bevel gear, and pinion shaft.
    G13592366Courtesy of SUBARU OF AMERICA, INC.
  2. Measure the backlash between the differential bevel gear and differential bevel pinion, and select a washer.
    1. Install the ST to the differential case.
      NOTE: The ST is a SUBARU genuine part.

      Preparation tool: 

      ST: Axle shaft (38415AA070)

    2. Using a dial gauge and a magnet stand, measure the backlash by inserting the dial gauge through the window of differential case.
      NOTE: When measuring, fix the differential bevel pinion in place with a screwdriver covered with cloth, or a similar tool.

      Specification: 

      0.13 - 0.18 mm (0.0051 - 0.0071 in)

      G13592367Courtesy of SUBARU OF AMERICA, INC.
    3. If the value is not within specification, select a suitable washer and replace it.
  3. Align the pinion shaft and differential case holes, and install a new spring pin to the position shown in the figure.
    G13226021Courtesy of SUBARU OF AMERICA, INC.
  4. Using the ST1, ST2 and a press, install the side bearing inner race.

    Preparation tool: 

    ST1: BUSHING 1-2 INSTALLER (499277100)

    ST2: SEAT (398497701)

    G11256006Courtesy of SUBARU OF AMERICA, INC.
Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote Shield Pro

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.