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AT Main Case: Installation

  1. Apply ATF to the lips of the low & reverse brake piston, and install the piston.
    NOTE: Take care not to damage the lip seal.
    Fig 1: Installing Low & Reverse Brake Piston
    G07665727Courtesy of SUBARU OF AMERICA, INC.
  2. Install the return spring.
    Fig 2: Installing Return Spring
    G07665728Courtesy of SUBARU OF AMERICA, INC.
  3. Install the spring retainer.
    Fig 3: Installing Spring Retainer
    G07665729Courtesy 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: Tightening Transmission Case Socket Bolts
    G07665730Courtesy 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 the retaining plate, and read its scale.
    NOTE: The value, which is read in the dial 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: Setting Dial Gauge To Retaining Plate
    G07665731Courtesy 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: Pressing Center Of Retaining Plate
    G07665732Courtesy 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: Snap Ring
    G07665733Courtesy of SUBARU OF AMERICA, INC.
  15. Apply compressed air intermittently to check for operation.
    Fig 8: Applying Compressed Air
    G07665734Courtesy 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: Measuring Clearance Between Shims
    G07665735Courtesy of SUBARU OF AMERICA, INC.
  17. Piston stroke calculation

    Calculate from the recorded dimension A and B, and if the service limit is exceeded, replace the drive plate with a new part, and select a retaining plate to make an adjustment so that it is within standard.

    T = A + B

    T: Piston stroke

    A: Amount of drive plate compression

    B: Clearance between retaining plate and snap ring

    Non-turbo model 

    Initial standard: 

    2.15 - 2.65 mm (0.085 - 0.104 in) 

    Limit thickness: 

    2.95 mm (0.116 in) 

    Turbo model 

    Initial standard: 

    2.70 - 3.20 mm (0.106 - 0.126 in) 

    Limit thickness: 

    3.90 mm (0.154 in) 

    PARTS THICKNESS SPECIFICATION CHART

    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: Leaf Spring
    G07665736Courtesy 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
    G07665737Courtesy of SUBARU OF AMERICA, INC.
  20. Install the 2-4 brake piston spring retainer to the transmission case.
    Fig 12: Installing 2-4 Brake Piston Spring Retainer To Transmission Case
    G07665738Courtesy 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: Positioning Snap Ring In Transmission
    G07665739Courtesy of SUBARU OF AMERICA, INC.
  22. Install the planetary gear and low clutch assembly to the transmission case.
    NOTE: Install carefully while rotating the low clutch and planetary gear assembly slowly, being careful not to damage the seal ring.
    Fig 14: Installing Planetary Gear And Low Clutch Assembly To Transmission Case
    G07665740Courtesy of SUBARU OF AMERICA, INC.
  23. Measure the amount of drive plate compression and record that value, (non-turbo model)
    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 the clutch, and read its scale.
      NOTE: The value, which is read in the dial 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 kg (22.5 lb).
    4. Put the flat board on retaining plate.
      Fig 15: Measuring Amount Of Drive Plate Compression
      G07665741Courtesy 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: Pressing Center Of Retaining Plate
      G07665742Courtesy of SUBARU OF AMERICA, INC.
  24. Install pressure rear plate, drive plate of 2-4 brake, driven plate, retaining plate, and snap ring.
    Fig 17: Retaining Plate, Drive Plate And Driven Plate
    G07665743Courtesy of SUBARU OF AMERICA, INC.
  25. Install a new 2-4 brake seal to the transmission case.
    Fig 18: Locating 2-4 Brake Seal
    G07665744Courtesy 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 Into 2-4 Brake
    G07665745Courtesy of SUBARU OF AMERICA, INC.
  27. Check the piston stroke, (non-turbo model)
    1. Measure clearance "B" between the retaining plate and snap ring.

      At this time, do not press down the retaining plate.

      Fig 20: Measuring Clearance "B" Between Retaining Plate And Snap Ring
      G07665746Courtesy of SUBARU OF AMERICA, INC.
    2. Piston stroke calculation

      Calculate with A and B dimensions recorded before. If the calculated value exceeds the service limits, replace the drive plate and select and adjust the retaining plate to be within standard values.

      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) 

      PARTS THICKNESS SPECIFICATION CHART

      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. Check the clearance between the retaining plate and snap ring, (turbo model)
    NOTE: If the clearance exceeds the service limits, replace the driven plate and select and adjust the retaining plate to make the clearance fall within initial standard values.

    Initial standard: 

    0.8 - 1.2 mm (0.031 - 0.047 in) 

    Limit thickness: 

    1.5 mm (0.059 in) 

    Fig 21: Clearance Between Retaining Plate And Snap Ring
    G07665747Courtesy of SUBARU OF AMERICA, INC.
    PARTS THICKNESS SPECIFICATION CHART

    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)
  29. Install the thrust needle bearing in the correct direction.
    Fig 22: Thrust Needle Bearing And Snap Ring
    G07665748Courtesy of SUBARU OF AMERICA, INC.
  30. Install the front sun gear and the thrust needle bearing.
    Fig 23: Front Sun Gear And Thrust Needle Bearing
    G07665749Courtesy 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.
  32. Install the thrust needle bearing in the correct direction.
    Fig 24: High Clutch Hub And Thrust Needle Bearing
    G07665750Courtesy of SUBARU OF AMERICA, INC.
  33. Install the high clutch assembly and reverse clutch assembly.
    Fig 25: High Clutch Assembly And Reverse Clutch Assembly
    G07665751Courtesy of SUBARU OF AMERICA, INC.
  34. Adjust the total end play. < Ref. to ADJUSTMENT , Oil Pump Housing. >
  35. Install the thrust needle bearing in the correct direction.
    Fig 26: Thrust Needle Bearing, High Clutch Assembly And Reverse Clutch Assembly
    G07665752Courtesy of SUBARU OF AMERICA, INC.
  36. Install a new gasket along with the oil pump housing assembly. < Ref. to INSTALLATION , Oil Pump Housing. >
  37. Install the converter case to the transmission case assembly. < Ref. to INSTALLATION , Converter Case. >
  38. Insert the inhibitor switch connector and transmission harness connector onto the stay.
    Fig 27: Inhibitor Switch Connector And Transmission Harness Connector
    G07665753Courtesy of SUBARU OF AMERICA, INC.
  39. Install the air breather hose. < Ref. to INSTALLATION , Air Breather Hose. >
  40. Install the ATF cooler pipe. < Ref. to INSTALLATION , ATF Cooler Pipe and Hose. >
  41. Install the oil charge pipe together with an O-ring. < Ref. to INSTALLATION , Oil Charge Pipe. >
  42. Apply ATF to the O-ring, insert the input shaft while rotating the shaft slowly by hand, and check the amount of protrusion.
    NOTE: Use new O-rings.

    Normal protrusion A: 

    50 - 55 mm (1.97 - 2.17 in) 

    Fig 28: Input Shaft (Protrusion A)
    G07665754Courtesy of SUBARU OF AMERICA, INC.
  43. Install the torque converter clutch assembly. < Ref. to INSTALLATION , Torque Converter Clutch Assembly. >
  44. Install the transmission assembly to the vehicle. < Ref. to INSTALLATION , Automatic Transmission Assembly. >