LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Subaru >> 2019 >> BRZ Limited, Automatic Trans >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Automatic Transaxle (Service Information) >> Automatic Transmission Unit >> Unit Inspection
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Unit Inspection

  1. Check of 1st & reverse brake return spring SUB-ASSY
    1. Measure the free length of the spring including the spring seat.

      Normal free length: 23.74mm {0.935in}

      If the measured free length is shorter than the normal free length, replace the 1st & reverse brake return spring SUB-ASSY.

      G12587727Courtesy of SUBARU OF AMERICA, INC.
    2. Check of rear planetary gear ASSY
      1. Use a feeler gauge to measure the rear planetary gear pinion thrust clearance.

        Normal clearance: 0.2 to 0.6 mm {0.00788 to 0.0236 in}

        If the measured clearance is larger than the normal clearance, replace the rear planetary gear ASSY.

        G12587728Courtesy of SUBARU OF AMERICA, INC.
      2. Measure the inner diameter of the rear planetary gear bushing.

        Normal inner diameter: 18.025mm {0.710in}

        If the measured inner diameter is larger than the normal inner diameter, replace the rear planetary gear ASSY.

        G12587729Courtesy of SUBARU OF AMERICA, INC.
    3. Check of No. 4 brake pack clearance
      1. Apply compressed air (392 kPa {4.0 kgf/cm2 , 57 psi}), release the air gun, and then check that the 1st & reverse brake piston moves smoothly.
        G12587730Courtesy of SUBARU OF AMERICA, INC.
      2. Measure the height difference (dimension A) between the upper surface of the brake apply tube and the No. 4 brake flange contact surface at both ends of the diameter of the 1st & reverse brake piston, and calculate the average.
        CAUTION: The 1st & reverse brake piston must be installed to the end face of the transmission case securely.
        NOTE: Dimension A = 23.32 to 24.18 mm {0.919 to 0.951 in}
        G12587731Courtesy of SUBARU OF AMERICA, INC.
      3. While applying a pressure of 4.9 N {0.5 kgf, 1.1 lbf} or less, use a caliper to measure the total thickness of the 2 No. 4 brake flanges, 4 No. 4 brake plates, and 5 No. 4 brake discs (dimension B) at both ends of the diameter, and calculate the average.
        NOTE: Dimension B = 23.64 to 26.00 mm {0.931 to 1.023 in}
        Pack clearance = dimension A - dimension B - 0.18 mm {0.0071 in} + 1.8 mm {0.0709 in}
        Pack clearance: 0.5 to 0.8 mm {0.0197 to 0.0315in}
      4. If the pack clearance is out of the normal range, select a No. 4 brake flange with the pack clearance within the normal range and install it.
        NOTE: There are 10 types of No. 4 brake flanges that can be used for pack clearance adjustment. Select the one with the most suitable thickness.
        G12587732Courtesy of SUBARU OF AMERICA, INC.

      Thickness H

      Part number Mark Thickness H
      30098AC170 0 0mm {0in}
      30098AC180 1 0.17mm {0.00669in}
      30098AC190 3 0.31mm {0.0122in}
      30098AC200 4 0.45mm {0.0177in}
      30098AC210 5 0.59mm {0.0232in}
      30098AC220 7 0.73mm {0.0287in}
      30098AC230 8 0.87mm {0.0342in}
      30098AC240 10 1.01mm {0.0397in}
      30098AC250 11 1.15mm {0.0452in}
      30098AC260 12 1.29mm {0.0507in}
    4. Check of No. 4 brake disc
      1. Check for wear and seizing on the sliding surfaces of the disc, plate, and flange.

        Replace them as required.

        CAUTION:
        • If the disc lining is peeling or discolored, or if even a part of the printed number is damaged, replace the all discs.
        • Soak new discs in ATF for at least 15 minutes before the assembly.
        G12587733Courtesy of SUBARU OF AMERICA, INC.
    5. Check of intermediate shaft
      1. Use a dial gauge to check the runout of the intermediate shaft.

        Normal runout: 0.03mm {0.00118in}

        If the runout is larger than the normal value, replace the intermediate shaft with a new one.

        G12587734Courtesy of SUBARU OF AMERICA, INC.
      2. Use a micrometer to check the outer diameters of the intermediate shaft at the positions shown in the figure.

        Normal diameter:

        1. 22.962 to 22.975mm {0.9041 to 0.9045in}
        2. 27.759 to 27.775mm {1.0929 to 1.0935in}

        If the outer diameter is smaller than the normal value, replace the intermediate shaft with a new one.

        G12587735Courtesy of SUBARU OF AMERICA, INC.
    6. Check of No. 3 one-way clutch ASSY
      1. Hold the rear planetary ring gear flange SUB-ASSY and turn the No. 3 one-way clutch ASSY.
        G12587736Courtesy of SUBARU OF AMERICA, INC.
      2. Check that when the No. 3 one-way clutch ASSY is turned counterclockwise it turns freely, whereas when it is turned clockwise it is locked.

        If any malfunction is found in the No. 3 one-way clutch ASSY, replace it.

    7. Check of center planetary gear ASSY
      1. Measure the center planetary gear pinion thrust clearance.

        Normal clearance: 0.12 to 0.68mm {0.00473 to 0.0267in}

        If the measured clearance is larger than the normal clearance, replace the center planetary gear ASSY.

        G12587737Courtesy of SUBARU OF AMERICA, INC.
    8. Check of No. 2 brake disc
      1. Check for wear and seizing on the sliding surfaces of the disc, plate, and flange.

        Replace them as required.

        CAUTION:
        • If the disc lining is peeling or discolored, or if even a part of the printed number is damaged, replace the all discs.
        • Soak new discs in ATF for at least 15 minutes before the assembly.
        G12587738Courtesy of SUBARU OF AMERICA, INC.
    9. Check of No. 2 brake piston return spring SUB-ASSY
      1. Measure the free length of the spring including the spring seat.

        Normal free length: 22.66mm {0.892in}

        If the measured free length is shorter than the normal free length, replace the No. 2 brake piston return spring SUB-ASSY.

        G12587739Courtesy of SUBARU OF AMERICA, INC.
    10. Check of piston stroke of No. 2 brake piston
      1. Apply compressed air (392 kPa {4.0 kgf/cm2 , 57 psi}), release the air gun, and then check that the No. 2 brake piston moves smoothly.
        G12587740Courtesy of SUBARU OF AMERICA, INC.
      2. While blowing compressed air (392 kPa {4.0 kgf/cm2 , 57 psi}) into the oil hole as shown in the figure, use the SST to measure the piston stroke of the No. 2 brake piston (distance A) at both ends of the diameter, and calculate the average.

        SST 09350-06120

        Piston stroke: 0.6 to 0.9mm {0.0237 to 0.0354in}

      3. If the piston stroke is out of the normal range, select a No. 2 brake flange with the piston stroke within the normal range and install it.
        NOTE: There are 8 types of No. 2 brake flanges that can be used for piston stroke adjustment. Select the one with the most suitable thickness.
        G12587741Courtesy of SUBARU OF AMERICA, INC.

      Flange thickness

      Part number Mark Thickness
      30098AB230 0 2.0mm {0.0787in}
      30098AB240 1 2.1mm {0.0827in}
      30098AB250 2 2.2mm {0.0866in}
      30098AB260 3 2.3mm {0.0906in}
      30098AB270 4 2.4mm {0.0945in}
      30098AB280 5 2.5mm {0.0984in}
      30098AB290 6 2.6mm {0.102in}
      30098AB300 7 2.7mm {0.106in}
    11. Check of brake piston return spring SUB-ASSY
      1. Measure the free length of the spring including the spring seat.

        Normal free length: 17.05mm {0.671in}

        If the measured free length is shorter than the normal free length, replace the brake piston return spring SUB-ASSY.

        G12587742Courtesy of SUBARU OF AMERICA, INC.
    12. Check of front planetary gear ASSY
      1. Measure the front planetary gear pinion thrust clearance.

        Normal clearance: 0.20 to 0.60mm {0.00788 to 0.0236in}

        If the measured clearance is larger than the normal clearance, replace the front planetary gear ASSY.

        G12587743Courtesy of SUBARU OF AMERICA, INC.
      2. Measure the inner diameter of the front planetary gear bushing.

        Normal inner diameter: 48.78mm {1.92in}

        If the measured inner diameter is larger than the normal inner diameter, replace the front planetary gear ASSY.

        G12587744Courtesy of SUBARU OF AMERICA, INC.
    13. Check of one-way clutch ASSY
      1. Install the one-way clutch ASSY to the one-way clutch inner race SUB-ASSY.
        G12587745Courtesy of SUBARU OF AMERICA, INC.
      2. Hold the one-way clutch inner race SUB-ASSY and turn the oneway clutch ASSY.
      3. Check that when the one-way clutch ASSY is turned counterclockwise it turns freely, whereas when it is turned clockwise it is locked.

        If any malfunction is found in the one-way clutch ASSY, replace it.

      4. Remove the one-way clutch ASSY from the one-way clutch inner race SUB-ASSY.
    14. Check of piston stroke of No. 1 brake piston
      1. Blow compressed air (392 kPa {4.0 kgf/cm2 , 57 psi}), release the air gun, and then check that the No. 1 brake piston moves smoothly.
        G12587746Courtesy of SUBARU OF AMERICA, INC.
      2. While applying a pressure of 4.9 N {0.5 kgf, 1.1 lbf} or less, measure height difference between the upper surface of the No. 1 brake piston and the No. 1 brake flange contact surface (dimension A) at both ends of the diameter of the No. 1 brake piston.
      3. Measure the total thickness of the No. 1 brake flange, 3 No. 1 brake plates, and 3 No. 1 brake discs (dimension B) at both ends of the diameter, and calculate the average.
        NOTE: Dimension A = 15.27 to 15.92 mm {0.602 to 0.626 in}
        Dimension B = 14.50 to 15.54 mm {0.571 to 0.611 in}
        Piston stroke = dimension A - dimension B
        Piston stroke: 0.42 to 0.72mm {0.0166 to 0.0283in}
      4. If the piston stroke is out of the normal range, the parts may be assembled incorrectly. Check them and assemble again.
      5. If the piston stroke is still out of the normal range, select another No. 1 brake flange with the piston stroke within the normal range.
        NOTE: There are 4 types of No. 1 brake flanges that can be used for piston stroke adjustment. Select the one with the most suitable thickness.
        G12587747Courtesy of SUBARU OF AMERICA, INC.

      Flange thickness

      Part number Mark Thickness
      30098AB170 0 2.0mm {0.0787in}
      30098AB180 1 2.2mm {0.0866in}
      30098AB190 2 2.4mm {0.0945in}
      30098AB200 3 2.6mm {0.102in}
    15. Check of No. 1 brake disc
      1. Check for wear and seizing on the sliding surfaces of the disc, plate, and flange.

        Replace them as required.

        CAUTION:
        • If the disc lining is peeling or discolored, or if even a part of the groove is damaged, replace the all discs.
        • Soak new discs in ATF for at least 15 minutes before the assembly.
        G12587748Courtesy of SUBARU OF AMERICA, INC.
    16. Check of No. 3 brake piston return spring SUB-ASSY
      1. Measure the free length of the spring including the spring seat.

        Normal free length: 15.72mm {0.619in}

        If the measured free length is shorter than the normal free length, replace the No. 3 brake piston return spring set SUB-ASSY.

        G12587749Courtesy of SUBARU OF AMERICA, INC.
    17. Check of No. 3 brake disc set
      1. Check for wear and seizing on the sliding surfaces of the disc, plate, and flange.

        Replace them as required.

        CAUTION:
        • If the disc lining is peeling or discolored, or if even a part of the printed number is damaged, replace the all discs.
        • Soak new discs in ATF for at least 15 minutes before the assembly.
        G12587750Courtesy of SUBARU OF AMERICA, INC.
    18. Check of No. 2 one-way clutch ASSY
      1. Hold the reverse clutch hub SUB-ASSY and turn the No. 2 one-way clutch ASSY.
        G12587751Courtesy of SUBARU OF AMERICA, INC.
      2. Check that when the No. 2 one-way clutch ASSY is turned clockwise it turns freely, whereas when it is turned counterclockwise it is locked.

        If any malfunction is found in the No. 2 one-way clutch ASSY, replace it.

    19. Operation check of each piston
      1. Check the operation sound while blowing compressed air into the oil hole shown in the figure.
        *a No. 1 clutch
        *b No. 2 clutch
        *c No. 3 clutch
        *d No. 4 clutch
        *e No. 1 brake
        *f No. 2 brake
        *g No. 3 brake
        *h No. 4 brake (in)
        *i No. 4 brake (out)
        G12587752Courtesy of SUBARU OF AMERICA, INC.
        NOTE: When checking the direct clutch, check the operation sound with the C3 accumulator piston hole closed.

        If no sound is heard, disassemble the parts and check their installation conditions.

    20. Check of No. 4 one-way clutch ASSY
      1. Hold the coast clutch hub SUB-ASSY and turn the No. 4 one-way clutch ASSY.
        G12587753Courtesy of SUBARU OF AMERICA, INC.
      2. Check that when the No. 4 one-way clutch ASSY is turned clockwise it turns freely, whereas when it is turned counterclockwise it is locked.

        If any malfunction is found in the No. 4 one-way clutch ASSY, replace it.

    21. Check of direct clutch return spring SUB-ASSY
      1. Measure the free length of the spring including the spring seat.

        Normal free length: 20.02mm {0.788in}

        If the measured free length is shorter than the normal free length, replace the direct clutch return spring SUB-ASSY.

        G12587754Courtesy of SUBARU OF AMERICA, INC.
    22. Check of reverse clutch return spring SUB-ASSY
      1. Measure the free length of the spring including the spring seat.

        Normal free length: 21.03mm {0.828in}

        If the measured free length is shorter than the normal free length, replace the reverse clutch return spring SUB-ASSY.

        G12587755Courtesy of SUBARU OF AMERICA, INC.
    23. Check of No. 2 clutch disc (direct clutch disc)
      1. Check for wear and seizing on the sliding surfaces of the disc, plate, and flange.

        Replace them as required.

        CAUTION:
        • If the disc lining is peeling or discolored, or if even a part of the printed number is damaged, replace the all discs.
        • Soak new discs in ATF for at least 15 minutes before the assembly.
        G12587756Courtesy of SUBARU OF AMERICA, INC.
    24. Check of No. 2 clutch pack clearance
      1. While blowing compressed air (392 kPa {4.0 kgf/cm2 , 57 psi}) into the oil hole as shown in the figure, use a dial gauge to measure the travel distance of the direct clutch flange (distance A) at both ends of the diameter, and calculate the average.
        NOTE: Flange travel distance A = 0.24 to 1.12 mm {0.00944 to 0.0440 in}
        Pack clearance = flange travel distance A - 0.03mm {0.00118in}
        Pack clearance: 0.5 to 0.8 mm {0.0197 to 0.0314 in}
        CAUTION: When measuring the travel distance, install a normal flange (3.4 mm {0.134 in} thick) to the position indicated with shadow in the figure.
      2. If the pack clearance is out of the normal range, select a direct clutch flange with the pack clearance within the normal range and install it.
        NOTE: There are 9 types of direct clutch flanges that can be used for pack clearance adjustment. Select the one with the most suitable thickness.
        G12587757Courtesy of SUBARU OF AMERICA, INC.

      Flange thickness

      Part number Mark Thickness
      30098AB080 0 3.0mm {0.118in}
      30098AB090 1 3.1mm {0.122in}
      30098AB100 2 3.2mm {0.126in}
      30098AB110 3 3.3mm {0.130in}
      30098AB120 4 3.4mm {0.134in}
      30098AB130 5 3.5mm {0.138in}
      30098AB140 6 3.6mm {0.142in}
      30098AB150 7 3.7mm {0.146in}
      30098AB160 8 3.8mm {0.150in}
    25. Check of No. 3 clutch pack clearance
      1. While blowing compressed air (392 kPa {4.0 kgf/cm2 , 57 psi}) into the oil hole as shown in the figure, use a dial gauge to measure the reverse clutch piston stroke (distance A) and the travel distance of the reverse clutch flange (distance B) at both ends of the diameter, and calculate the average.
        G12587758Courtesy of SUBARU OF AMERICA, INC.
        NOTE: Piston stroke A = 1.62 to 2.68 mm {0.0638 to 0.105 in}
        Flange travel distance B = 1.22 to 1.67 mm {0.0481 to 0.0657 in}
        Pack clearance = piston stroke A - flange travel distance B - 0.02 mm {0.000787 in}
        Pack clearance: 0.4 to 0.7mm {0.0158 to 0.0275in}
        CAUTION: When measuring the travel distance, install a normal flange (2.8 mm {0.110 in} thick) to the position indicated with shadow in the figure.
      2. If the pack clearance is out of the normal range, select a reverse clutch flange with the pack clearance within the normal range and install it.
        NOTE: There are 12 types of reverse clutch flanges that can be used for pack clearance adjustment. Select the one with the most suitable thickness.

      Flange thickness

      Part number Mark Thickness
      30098AA770 0 2.4mm {0.0945in}
      30098AA780 1 2.5mm {0.0984in}
      30098AA790 2 2.6mm {0.102in}
      30098AA800 3 2.7mm {0.106in}
      30098AA810 4 2.8mm {0.110in}
      30098AA820 5 2.9mm {0.114in}
      30098AA830 6 3.0mm {0.118in}
      30098AA840 7 3.1mm {0.122in}
      30098AA850 8 3.2mm {0.126in}
      30098AA860 9 3.3mm {0.130in}
      30098AA870 A 3.4mm {0.134in}
      30098AA880 B 3.5mm {0.138in}
    26. Check of forward clutch return spring SUB-ASSY
      1. Use a caliper gauge to measure the free length of the spring including the spring seat.

        Normal free length: 26.29mm {1.04in}

        If the measured free length is shorter than the normal free length, replace the forward clutch return spring SUB-ASSY.

        G12587759Courtesy of SUBARU OF AMERICA, INC.
    27. Check of No. 4 clutch disc (coast clutch disc)
      1. Check for wear and seizing on the sliding surfaces of the disc, plate, and flange.

        Replace them as required.

        CAUTION:
        • If the disc lining is peeling or discolored, or if even a part of the printed number is damaged, replace the all discs.
        • Soak new discs in ATF for at least 15 minutes before the assembly.
        G12587760Courtesy of SUBARU OF AMERICA, INC.
    28. Check of No. 1 clutch pack clearance
      1. While blowing compressed air (196 kPa {2.0 kgf/cm2 , 28 psi}) into the oil hole as shown in the figure, use a dial gauge to measure the travel distance of the forward clutch flange (distance A) at both ends of the diameter, and calculate the average.
        NOTE: Flange travel distance A = 0.14 to 0.17 mm {0.0055 to 0.0067 in}
        Pack clearance = flange travel distance A - 0.01 mm {0.0004 in}
        Pack clearance: 0.56 to 0.86mm {0.0221 to 0.0338in}
        CAUTION: When measuring the travel distance, install a normal flange (3.5 mm {0.138 in} thick) to the position indicated with shadow in the figure.
      2. If the pack clearance is out of the normal range, select a forward clutch flange with the pack clearance within the normal range and install it.
        NOTE: There are 10 types of forward clutch flanges that can be used for pack clearance adjustment. Select the one with the most suitable thickness.
        G12587761Courtesy of SUBARU OF AMERICA, INC.

      Flange thickness

      Part number Mark Thickness
      30098AA630 0 3.0mm {0.118in}
      30098AA640 1 3.1mm {0.122in}
      30098AA650 2 3.2mm {0.126in}
      30098AA670 3 3.3mm {0.130in}
      30098AA680 4 3.4mm {0.134in}
      30098AA690 5 3.5mm {0.138in}
      30098AA700 6 3.6mm {0.142in}
      30098AA710 7 3.7mm {0.146in}
      30098AA720 8 3.8mm {0.150in}
      30098AA730 9 3.9mm {0.154in}
    29. Check of No. 1 clutch disc (forward clutch disc)
      1. Check for wear and seizing on the sliding surfaces of the disc, plate, and flange.

        Replace them as required.

        CAUTION:
        • If the disc lining is peeling or discolored, or if even a part of the printed number is damaged, replace the all discs.
        • Soak new discs in ATF for at least 15 minutes before the assembly.
        G12587762Courtesy of SUBARU OF AMERICA, INC.
    30. Check of No. 4 clutch pack clearance
      1. While blowing compressed air (196 kPa {2.0 kgf/cm2, 28 psi}) into the oil hole as shown in the figure, use a dial gauge to measure the travel distance of the coast clutch flange (distance A) at both ends of the diameter, and calculate the average.
        NOTE: Flange travel distance A = 0.02 to 1.01mm {0.000787 to 0.0397in}
        Pack clearance = flange travel distance A - 0.01 mm {0.000394in}
        Pack clearance: 0.4 to 0.7mm {0.0158 to 0.0275in}
        CAUTION: When measuring the travel distance, install a normal flange (3.5 mm {0.0158 to 0.0275 in} thick) to the position indicated with shadow in the figure.
      2. If the pack clearance is out of the normal range, select a coast clutch flange with the pack clearance within the normal range and install it.
        NOTE: There are 10 types of coast clutch flanges that can be used for pack clearance adjustment. Select the one with the most suitable thickness.
        G12587763Courtesy of SUBARU OF AMERICA, INC.

      Flange thickness

      Part number Mark Thickness
      30098AA980 0 3.0mm {0.118in}
      30098AA990 1 3.1mm {0.122in}
      30098AB000 2 3.2mm {0.126in}
      30098AB010 3 3.3mm {0.130in}
      30098AB020 4 3.4mm {0.134in}
      30098AB030 5 3.5mm {0.138in}
      30098AB040 6 3.6mm {0.142in}
      30098AB050 7 3.7mm {0.146in}
      30098AB060 8 3.8mm {0.150in}
      30098AB070 9 3.9mm {0.154in}
    31. Check of forward clutch hub SUB-ASSY
      1. Use a caliper gauge to check the inner diameter of the forward clutch hub bushing.

        Normal inner diameter: 23.037 to 23.062mm {0.9070 to 0.9079in}

        If the measured inner diameter is longer than the normal inner diameter, replace the forward clutch hub SUB-ASSY.

        G12587764Courtesy of SUBARU OF AMERICA, INC.
    32. Check of No. 3 clutch disc
      1. Check for wear and seizing on the sliding surfaces of the disc, plate, and flange.

        Replace them as required.

        CAUTION:
        • If the disc lining is peeling or discolored, or if even a part of the printed number is damaged, replace the all discs.
        • Soak new discs in ATF for at least 15 minutes before the assembly.
        G12587765Courtesy of SUBARU OF AMERICA, INC.
    33. Check of reverse clutch hub SUB-ASSY
      1. Measure the inner diameter of the reverse clutch hub bushing.

        Normal inner diameter: 33.312 to 33.337mm {1.3115 to 1.3125in}

        If the measured inner diameter is longer than the normal inner diameter, replace the reverse clutch hub SUB-ASSY.

        G12587766Courtesy of SUBARU OF AMERICA, INC.
scientia non olet · About LEMON Manuals