2021 Subaru Forester BaseFACTORY OEM SERVICE PROCEDURE

Extension Case: Installation

  1. Select the transfer drive gear shim. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>Reduction Driven Gear>ADJUSTMENT .
  2. Select the transfer driven gear shim. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>Transfer Clutch>ADJUSTMENT .
  3. Attach the selected transfer drive gear shim to extension case with vaseline.
  4. Attach the selected transfer driven gear shim to extension case with vaseline.
  5. Install a new O-ring to the transmission case.
    NOTE: Apply CVTF to the O-rings.
  6. Apply liquid gasket to the mating surface of the extension case as shown in the figure, and temporarily install the extension case.
    NOTE:
    • Before applying liquid gasket, degrease the old liquid gasket seal surfaces of the extension case and transmission case.
    • Install within 5 min. after applying liquid gasket.

    Liquid gasket: 

    THREE BOND 1215B or equivalent

    G13225803Courtesy of SUBARU OF AMERICA, INC.
  7. Install the extension case to transmission hanger.

    Tightening torque: 

    25 N.m (2.5 kgf.m, 18.4 ft.lb)

  8. Install the electric oil pump. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>Electric Fluid Pump>INSTALLATION .
  9. Install the transmission body. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>Transmission Assembly>INSTALLATION .
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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.