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AT Main Case: Removal: Installation

  1. Install the low & reverse brake piston.
    NOTE:
    • Take care not to damage the lip seal.
    • Apply ATF to the lip.
      Fig 1: Removing/Installing Low & Reverse Brake Piston
      G05002754Courtesy of SUBARU OF AMERICA, INC.
  2. Install the return spring.
    Fig 2: Removing/Installing Return Spring
    G05002752Courtesy of SUBARU OF AMERICA, INC.
  3. Install the spring retainer.
    Fig 3: Removing/Installing Spring Retainer
    G05002751Courtesy of SUBARU OF AMERICA, INC.
  4. Install the one-way clutch inner race.
  5. Tighten the socket head bolts evenly from the rear side of transmission case.

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

    Fig 4: Removing/Installing Socket Head Bolts
    G05002750Courtesy of SUBARU OF AMERICA, INC.
  6. Place the front side of transmission body up.
  7. Install the thrust needle bearing.
  8. Place the dish plate, driven plate, drive plate and retaining plate neatly in this order on surface table.
  9. Set the dial gauge to retaining plate, and read its scale.
    NOTE: The value, which is read in the gauge at this time, is zero point.
  10. Scale and record the weight "Z" of the flat board that will be placed on the retaining plate.
    NOTE:
    • Use a stiff board which does not bend against load as a flat board to be put on retaining plate.
    • Use a flat board weighing less than 8.5 kgf (18.7 lb).
  11. Put the flat board on retaining plate.
    Fig 5: Positioning Flat Board On Retaining Plate
    G05002759Courtesy of SUBARU OF AMERICA, INC.
  12. Using the following formula, read the push/pull gauge, and calculate "N".

    N = 83 N (8.5 kgf, 18.7 lb)-Z

    N: Value indicated on push/pull gauge

    83 N (8.5 kgf, 18.7 lb): Load applied to clutch plate

    Z: Flat board weight

  13. Press the center of retaining plate with a force of N using a push/pull gauge, and measure and record height "A". Measure at three or more locations spaced by equal distances and take the average value.
    NOTE: If measuring in three locations, measure every 120°. If measuring in four locations, measure every 90°.
    Fig 6: Measuring Height A
    G06337399Courtesy of SUBARU OF AMERICA, INC.
  14. Installation of the low & reverse brake: Install the dish plate, driven plate, drive plate and retaining plate, and then secure them with a snap ring.
    NOTE: Pay attention to the orientation of the dish plate.
    Fig 7: Identifying Snap Ring
    G06337400Courtesy of SUBARU OF AMERICA, INC.
  15. Apply compressed air intermittently to check for operation.
    Fig 8: Applying Compressed Air For Checking Operation
    G06337401Courtesy of SUBARU OF AMERICA, INC.
  16. Place same thickness shims on both sides to prevent plate from tilting, then measure and record the clearance "B".
    NOTE: Do not push in the shim down with force to a point where the waves on the drive plate will be crushed.
    Fig 9: Identifying Clearance B
    G06337402Courtesy of SUBARU OF AMERICA, INC.
  17. Piston stroke calculation Calculate with A and B dimensions recorded before. If the calculated value exceeds the service limit, replace the drive plate with a new part and adjust it within the initial specification.

    T = A+B

    T: Piston stroke

    A: Amount of drive plate compression B: Clearance between retaining plate and snap ring

    Initial standard: 2.15 - 2.65 mm (0.085 - 0.104 in) 

    Limit thickness: 2.95 mm (0.116 in) 

    RETAINING PLATE THICKNESS SPECIFICATIONS

    Retaining plate
    Part No. Thickness mm (in)
    31667AA420 3.8(0.150)
    31667AA320 4.1 (0.161)
    31667AA330 4.4(0.173)
    31667AA340 4.7(0.185)
    31667AA350 5.0(0.197)
    31667AA360 5.3 (0.209)
    31667AA370 5.6 (0.220)
    31667AA380 5.9 (0.232)
  18. Install the leaf spring of the low & reverse brake.
    Fig 10: Identifying Leaf Spring
    G06337403Courtesy of SUBARU OF AMERICA, INC.
  19. Install the 2-4 brake piston and 2-4 brake retainer by aligning the hole of the 2-4 brake retainer with the hole on the transmission case.
    Fig 11: Installing 2-4 Brake Piston And 2-4 Brake Retainer
    G06337404Courtesy of SUBARU OF AMERICA, INC.
  20. Install the 2-4 brake piston spring retainer to the transmission case.
    Fig 12: Removing/Installing 2-4 Brake Spring Retainer
    G05002745Courtesy of SUBARU OF AMERICA, INC.
  21. Position the snap ring in the transmission. Using ST, press the snap ring into the specified location.

    ST 498677100. COMPRESSOR

    Fig 13: Pressing Snap Ring Using ST 498677100 Compressor
    G05002767Courtesy of SUBARU OF AMERICA, INC.
  22. Install the planetary gear and low clutch assembly to the transmission case.
    NOTE: When installing the low clutch and planetary gear assembly while rotating them, rotate them slowly and pay attention not to damage the seal ring.
    Fig 14: Removing/Installing Planetary Gear And Low Clutch Assembly
    G05002742Courtesy of SUBARU OF AMERICA, INC.
  23. Measure the amount of drive plate compression and record that value.
    1. Place the dish plate, driven plate, drive plate and retaining plate neatly in this order on surface table.
    2. Set the dial gauge to retaining plate, and read its scale.
      NOTE: The value, which is read in the gauge at this time, is zero point.
    3. Scale and record the weight "Z" of the flat board that will be placed on the retaining plate.
      NOTE:
      • Use a stiff board which does not bend against load as a flat board to be put on retaining plate.
      • Use a flat board weighing less than 10.2 kgf (22.5 lb).
    4. Put the flat board on retaining plate.
      Fig 15: Positioning Flat Board On Retaining Plate
      G05002759Courtesy of SUBARU OF AMERICA, INC.
    5. Using the following formula, read the push/pull gauge, and calculate "N".

      N = 100 N (10.2 kgf, 22.5 lb) - Z

      N: Value indicated on push/pull gauge

      100 N (10.2 kgf, 22.5 lb): Load applied to clutch plate

      Z: Flat board weight

    6. Press the center of retaining plate with a force of N using a push/pull gauge, and measure and record height "A". Measure at three or more locations spaced by equal distances and take the average value.
      NOTE: If measuring in three locations, measure every 120°. If measuring in four locations, measure every 90°.
      Fig 16: Measuring Height A
      G06337409Courtesy of SUBARU OF AMERICA, INC.
  24. Install pressure plate, drive plate of 2-4 brake, driven plate, retaining plate, and snap ring.
    Fig 17: Identifying Retaining Plate, Drive Plate And Driven Plate Of 2-4 Brake
    G05002741Courtesy of SUBARU OF AMERICA, INC.
  25. Install a new 2-4 brake oil seal to the transmission case.
    Fig 18: Locating 2-4 Brake Oil Seal
    G05956186Courtesy of SUBARU OF AMERICA, INC.
  26. After all 2-4 brake component parts have been installed, blow in air intermittently and confirm the operation of the brake.
    Fig 19: Blowing Air For Checking Operation Of Brake
    G05002771Courtesy of SUBARU OF AMERICA, INC.
  27. Check the piston stroke.
    1. Measure clearance "B" between the retaining plate and snap ring. At this time, do not press down the retaining plate.
      Fig 20: Identifying Clearance B Between Retaining Plate And Snap Ring
      G06337413Courtesy of SUBARU OF AMERICA, INC.
    2. Piston stroke calculation Calculate with A and B dimensions recorded before. If the calculated value exceeds the service limit, replace the drive plate with a new part and adjust it within the initial specification.

      T = A + B

      T: Piston stroke

      A: Amount of drive plate compression B: Clearance between retaining plate and snap ring

      Initial standard: 

      1.7-2.1 mm (0.067 - 0.083 in) 

      Limit thickness: 2.3 mm (0.091 in) 

      RETAINING PLATE THICKNESS SPECIFICATIONS

      Retaining plate
      Part No. Thickness mm (in)
      31567AA991 5.6 (0.220)
      31567AB001 5.8 (0.228)
      31567AB011 6.0 (0.236)
      31567AB021 6.2 (0.244)
      31567AB031 6.4 (0.252)
      31567AB041 6.6 (0.260)
  28. Be careful not to mistake the location of the leaf spring to be installed.
    Fig 21: Identifying Leaf Spring And Retaining Plate
    G06337414Courtesy of SUBARU OF AMERICA, INC.
  29. Install the thrust needle bearing in the correct direction.
    Fig 22: Position Of Installing Thrust Needle Bearing
    G06337415Courtesy of SUBARU OF AMERICA, INC.
  30. Install the front sun gear and the thrust needle bearing.
    Fig 23: Position Of Installing Front Sun Gear And Thrust Needle Bearing
    G06337416Courtesy of SUBARU OF AMERICA, INC.
  31. Apply Vaseline, and attach the thrust needle bearing to the high clutch hub, then engage the splines of the front planetary carrier correctly to install the high clutch hub.
    Fig 24: Position Of Installing High Clutch Hub
    G06337417Courtesy of SUBARU OF AMERICA, INC.
  32. Install the thrust needle bearing in the correct direction.
    Fig 25: Identifying High Clutch And Reverse Clutch Assembly
    G06337418Courtesy of SUBARU OF AMERICA, INC.
  33. Install the high clutch assembly and reverse clutch assembly.
  34. Adjust the total end play. Refer to ADJUSTMENT , Oil Pump Housing.
  35. Install the thrust needle bearing in the correct direction.
    Fig 26: Position Of Installing Thrust Needle Bearing
    G06337419Courtesy of SUBARU OF AMERICA, INC.
  36. Install a new gasket along with the oil pump housing assembly. Refer to INSTALLATION , Oil Pump Housing.
  37. Install the converter case to the transmission case assembly. Refer to INSTALLATION , Converter Case.
  38. Insert the inhibitor switch connector and transmission harness connector onto the stay.
    Fig 27: Identifying Inhibitor Switch And Transmission Harness Connector
    G06337420Courtesy of SUBARU OF AMERICA, INC.
  39. Install the air breather hose. Refer to INSTALLATION , Air Breather Hose.
  40. Install the ATF cooler pipe. Refer to INSTALLATION , ATF Cooler Pipe and Hose.
  41. Install the oil charge pipe together with an O-ring. Refer to INSTALLATION , Oil Charge Pipe.
  42. Insert the input shaft while rotating it lightly by hand, and then check the amount of protrusion.

    Normal protrusion A: 50 - 55 mm (1.97-12.17 in) 

    Fig 28: Identifying Input Shaft Normal Protrusion A
    G06337421Courtesy of SUBARU OF AMERICA, INC.
  43. Install the torque converter clutch assembly. Refer to INSTALLATION , Torque Converter Clutch Assembly.
  44. Install the transmission assembly to the vehicle. Refer to INSTALLATION , Automatic Transmission Assembly.
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