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Automatic Transmission Unit: Inspection

  1. INSPECT 1st AND REVERSE BRAKE RETURN SPRING SUB-ASSEMBLY 
    1. Using a vernier caliper, measure the free length of the spring together with the spring seat.

      Standard free length: 23.74 mm (0.935 in.) 

      If the free length is shorter than the standard free length, replace the brake piston return spring sub-assembly.

      Fig 1: Measuring Free Length Of Spring
      G05289918Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. INSPECT REAR PLANETARY GEAR ASSEMBLY 
    1. Using a feeler gauge, measure the rear planetary gear pinion thrust clearance.

      Standard clearance: 0.2 to 0.6 mm (0.008 to 0.024 in.) 

      If the clearance is not as specified, replace the planetary gear assembly.

      Fig 2: Measuring Rear Planetary Gear Pinion Thrust Clearance
      G05289919Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using a caliper gauge, measure the inside diameter of the rear planetary gear bushing.

      Standard inside diameter: 20.025 mm (0.7884 in.) 

      If the inside diameter is not as specified, replace the rear planetary gear assembly.

      Fig 3: Measuring Inside Diameter Of Rear Planetary Gear Bushing
      G05289920Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. INSPECT PACK CLEARANCE OF 1st AND REVERSE BRAKE PISTON 
    1. Make sure that the 1st and reverse brake piston moves smoothly while applying compressed air intermittently into the transmission case.
      Fig 4: Applying Compressed Air Into Transmission Case
      G05289921Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using a vernier caliper, measure the level difference (length A) between the upper surface of the brake apply tube and the hitting surface of the No. 4 brake flange at both ends across the 1st and reverse brake piston diameter, and calculate the average.
      NOTE: The 1st and reverse brake piston must be securely installed to the end face of the transmission case.

      HINT:

      Length A = 22.05 to 22.91 mm (0.8681 to 0.9020 in.)

      Fig 5: Measuring Level Difference (Length A) Between Upper Surface Of Brake
      G05289922Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Using a vernier caliper, measure the combined thickness (length B) of the brake flanges, the 4 brake plates and the 4 brake discs at both ends across the diameter, and calculate the average.

      HINT:

      Length B = 23.11 to 23.89 mm (0.9098 to 0.9405 in.)

      Pack clearance = Length A - Length B - 0.22 mm to 1.8 mm (0.0087 to 0.071 in.)

      Standard pack clearance: 0.4 to 0.7 mm (0.016 to 0.028 in.) 

      Fig 6: Measuring Combined Thickness (Length B) Of Brake Flanges, Brake Plates And Brake Discs
      G05289923Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. If the pack clearance is outside the standard, select and install a brake flange that brings the pack clearance within the standard.

      HINT:

      There are 8 types of flanges that can be used to adjust the pack clearance. Select the one with the most appropriate thickness.

      Standard thickness H 

      THICKNESS REFERENCE CHART

      No. Thickness H No. Thickness H
      0 0 mm (0 in.) 8 0.8 mm (0.03150 in.)
      2 0.2 mm (0.00787 in.) 10 1.0 mm (0.03937 in.)
      4 0.4 mm (0.01575 in.) 12 1.2 mm (0.04724 in.)
      6 0.6 mm (0.02362 in.) 14 1.4 mm (0.05512 in.)
  4. INSPECT NO. 4 BRAKE DISC 
    1. Replace all discs if one of the following problems is present: 1) a disc, plate or flange is worn or burnt, 2) the lining of a disc is peeled off or discolored, or 3) grooves or printed numbers have even a little bit of damage.
      NOTE: Before assembling new discs, soak them in ATF for at least 15 minutes.
      Fig 7: Inspecting No. 4 Brake Disc
      G05289924Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. INSPECT INTERMEDIATE SHAFT 
    1. Using a dial indicator, measure the intermediate shaft runout.

      Maximum runout: 0.03 mm (0.0012 in.) 

      If the runout is greater than the maximum, replace the intermediate shaft.

      Fig 8: Measuring Intermediate Shaft Runout
      G05289925Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using a micrometer, measure the diameter of the intermediate shaft at each point shown in the illustration.

      Standard diameter 

      ITEM REFERENCE CHART

      Item Specified Condition
      A 25.962 to 25.975 mm (1.022 to 1.023 in.)
      B 25.962 to 25.975 mm (1.022 to 1.023 in.)
      C 32.062 to 32.075 mm (1.262 to 1.263 in.)
      D 32.062 to 32.075 mm (1.262 to 1.263 in.)

      If the diameter is not as specified, replace the intermediate shaft.

      Fig 9: Measuring Outer Diameter Of Intermediate Shaft
      G05289926Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. INSPECT REAR PLANETARY RING GEAR FLANGE SUB-ASSEMBLY 
    1. Using a caliper gauge, measure the inside diameter of the rear planetary ring gear bush.

      Standard inside diameter: 32.19 mm (1.2673 in.) 

      If the inside diameter is not as specified, replace the rear planetary ring gear flange sub-assembly.

      Fig 10: Measuring Inside Diameter Of Rear Planetary Ring Gear Bushing
      G05289927Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. INSPECT NO. 3 1-way CLUTCH ASSEMBLY 
    1. Hold the rear planetary ring gear flange and turn the 1-way clutch.
    2. Check that the 1-way clutch turns freely counterclockwise and locks clockwise.

      If there is a problem with the 1-way clutch, replace it.

      Fig 11: Inspecting No. 3 1-Way Clutch Assembly
      G05289928Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  8. INSPECT CENTER PLANETARY GEAR ASSEMBLY 
    1. Using a feeler gauge, measure the center planetary gear pinion thrust clearance.

      Standard clearance: 0.12 to 0.68 mm (0.005 to 0.027 in.) 

      If the clearance is not as specified, replace the center planetary gear assembly.

      Fig 12: Measuring Center Planetary Gear Pinion Thrust Clearance
      G05289929Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  9. INSPECT NO. 2 BRAKE DISC 
    1. Replace all discs if one of the following problems is present: 1) a disc, plate or flange is worn or burnt, 2) the lining of a disc is peeled off or discolored, or 3) grooves or printed numbers have even a little bit of damage.
      NOTE: Before assembling new discs, soak them in ATF for at least 15 minutes.
      Fig 13: Inspecting No. 3 Brake Disc
      G05289930Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  10. INSPECT NO. 2 BRAKE PISTON RETURN SPRING SUB-ASSEMBLY 
    1. Using a vernier caliper, measure the free length of the spring together with the spring seat.

      Standard free length: 22.66 mm (0.8921 in.) 

      If the free length is not as specified, replace the brake piston return spring sub-assembly.

      Fig 14: Measuring Free Length Of Spring
      G05289931Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  11. INSPECT PISTON STROKE OF NO. 2 BRAKE PISTON 
    1. Inspect the piston stroke of the brake piston.
      1. Make sure that the brake piston moves smoothly while applying compressed air intermittently into the transmission case.
        Fig 15: Applying Compressed Air Into Transmission Case
        G05289932Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Using SST and a dial indicator, measure the moving distance (distance A) of the clutch disc at both ends across the diameter while blowing air into the oil hole as shown in the illustration, and calculate the average.

        SST 09350-30020 (09350-06120) 

        Standard piston stroke: 0.6 to 0.9 mm (0.024 to 0.035 in.) 

      3. If the piston stroke is not as specified, select and install a brake flange that brings the piston stroke within the standard.

        HINT:

        There are 8 types of flanges that can be used to adjust the pack clearance. Select one with the most appropriate thickness.

        Fig 16: Measuring Moving Distance (Distance A) Of Clutch Disc
        G05289933Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard flange thickness 

        THICKNESS REFERENCE CHART

        No. Thickness
        0 2.0 mm (0.079 in.)
        1 2.1 mm (0.083 in.)
        2 2.2 mm (0.087 in.)
        3 2.3 mm (0.091 in.)
        4 2.4 mm (0.094 in.)
        5 2.5 mm (0.098 in.)
        6 2.6 mm (0.102 in.)
        7 2.7 mm (0.106 in.)
  12. INSPECT BRAKE PISTON RETURN SPRING SUB-ASSEMBLY 
    1. Using a vernier caliper, measure the free length of the spring together with the spring seat.

      Standard free length: 17.05 mm (0.671 in.) 

      If the free length is not as specified, replace the brake piston return spring.

      Fig 17: Measuring Free Length Of Spring
      G05289934Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  13. INSPECT FRONT PLANETARY GEAR ASSEMBLY 
    1. Using a feeler gauge, measure the front planetary pinion gear thrust clearance.

      Standard clearance: 0.20 to 0.60 mm (0.008 to 0.024 in.) 

      If the clearance is not as specified, replace the front planetary gear assembly.

      Fig 18: Measuring Front Planetary Pinion Gear Thrust Clearance
      G05289935Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using a cylinder gauge, measure the inside diameter of the front planetary gear bushing.

      Standard inside diameter: 57.43 mm (2.261 in.) 

      If the inside diameter is not as specified, replace the front planetary gear.

      Fig 19: Measuring Inside Diameter Of Front Planetary Gear Bushing
      G05289936Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  14. INSPECT 1-WAY CLUTCH ASSEMBLY 
    1. Install the 1-way clutch to the 1-way clutch inner race.
    2. Hold the 1-way clutch inner race and turn the 1-way clutch.
    3. Check that the 1-way clutch assembly turns freely counterclockwise and locks clockwise.

      If there is a problem with the 1-way clutch, replace it.

    4. Remove the 1-way clutch assembly from the 1-way clutch inner race.
      Fig 20: Checking 1-Way Clutch Assembly Turns Freely
      G05289937Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  15. INSPECT PISTON STROKE OF NO. 1 BRAKE PISTON 
    1. Inspect the piston stroke of the brake piston.
      1. Make sure the brake piston moves smoothly while applying compressed air intermittently into the transmission case.
        Fig 21: Applying Compressed Air Into Transmission Case
        G05289938Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Using a vernier caliper, measure the level difference (length A) between the upper surface of the brake piston and the hitting surface of the brake flange at both ends across the brake piston diameter.
      3. Using a vernier caliper, measure the thickness (length B) of the brake flange, the 3 brake plates and the 3 brake discs altogether at both ends across the diameter, and calculate the average.

        HINT:

        Length A = 15.29 to 15.77 mm (0.6020 to 0.6209 in.)

        Length B = 14.72 to 15.12 mm (0.5795 to 0.5953 in.)

        Piston stroke = Length A - Length B

        Standard piston stroke: 0.42 to 0.72 mm (0.017 to 0.028 in.) 

        Fig 22: Identifying Level Difference Between Upper Surface Of Brake Piston And Hitting Surface Of Brake Flange
        G05289939Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        If the piston stroke is not as specified, parts may have been assembled incorrectly, so check and reassemble them again. If the piston stroke is still outside the specification range, select another flange that brings the piston stroke within the specification.

        HINT:

        There are 4 different thicknesses for the flange that brings the piston stroke within the specification.

        Standard flange thickness 

        THICKNESS REFERENCE CHART

        No. Thickness
        0 2.0 mm (0.079 in.)
        1 2.2 mm (0.087 in.)
        2 2.4 mm (0.094 in.)
        3 2.6 mm (0.102 in.)
  16. INSPECT NO. 1 BRAKE DISC 
    1. Replace all discs if one of the following problems is present: 1) a disc, plate or flange is worn or burnt, 2) the lining of a disc is peeled off or discolored, or 3) grooves or printed numbers have even a little bit of damage.
      NOTE: Before assembling new discs, soak them in ATF for at least 15 minutes.
      Fig 23: Inspecting No. 1 Brake Disc
      G05289940Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  17. INSPECT NO. 3 BRAKE PISTON RETURN SPRING SUB-ASSEMBLY 
    1. Using a vernier caliper, measure the free length of the spring together with the spring seat.

      Standard free length: 15.72 mm (0.619 in.) 

      If the inside diameter is not as specified, replace the brake piston return spring.

      Fig 24: Measuring Free Length Of Spring
      G05289941Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  18. INSPECT 2nd BRAKE DISC SET 
    1. Replace all discs if one of the following problems is present: 1) a disc, plate or flange is worn or burnt, 2) the lining of a disc is peeled off or discolored, or 3) grooves or printed numbers have even a little bit of damage.
      NOTE: Before assembling new discs, soak them in ATF for at least 15 minutes.
      Fig 25: Inspecting 2nd Brake Disc
      G05289942Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  19. INSPECT NO. 2 1-WAY CLUTCH ASSEMBLY 
    1. Hold the reverse clutch hub and turn the 1-way clutch.
    2. Check that the 1-way clutch turns freely clockwise and locks counterclockwise.

      If there is a problem with the 1-way clutch, replace it.

      Fig 26: Checking 1-Way Clutch Turns Freely
      G05289943Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  20. INSPECT INDIVIDUAL PISTON OPERATION 
    1. Check the operating sound while applying compressed air into the oil holes indicated in the illustration.

      HINT:

      When inspecting the O/D direct clutch, check if with the C3 accumulator piston hole closed.

      If there is no sound, disassemble and check each parts installation condition.

      1. No. 2 clutch (C2)
      2. No. 4 clutch (C4)
      3. No. 3 clutch (C3)
      4. No. 1 clutch (C1)
      5. No. 3 brake (B3)
      6. No. 1 brake (B1)
      7. No. 2 brake (B2)
      8. No. 4 brake (B4)
        Fig 27: Identifying Clutch Points
        G05289944Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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