2021 Subaru Ascent BaseFACTORY OEM SERVICE PROCEDURE

Extension Case: Installation

  1. Clean the mating surface of the extension case and intermediate case.
  2. Select the thrust bearing. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>Rear Drive Shaft>ADJUSTMENT .
  3. Select the shim for transfer reduction driven gear. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>Transfer Reduction Driven Gear>ADJUSTMENT .
  4. Install the selected thrust bearing to transfer clutch.
    NOTE: Install the thrust bearing in the correct direction.
    G06654499Courtesy of SUBARU OF AMERICA, INC.
  5. Attach the selected shim to transfer reduction driven gear.
  6. Apply liquid gasket to the extension case seamlessly, and temporarily install it.

    Liquid gasket: 

    THREE BOND 1215B or equivalent

    G12476776Courtesy of SUBARU OF AMERICA, INC.
  7. Tighten the extension case mounting bolts and install the harness clips.

    Tightening torque: 

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

  8. Install the front wheel speed sensor. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>Front Wheel Speed Sensor>INSTALLATION .
  9. Install the transmission body. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>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.