Automatic Transmission Unit Inspection

Drivetrain. Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
A750F Automatic Transmission Transaxle. Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25

  1. INSPECT AUTOMATIC TRANSMISSION OIL PAN SUB-ASSEMBLY

  2. INSPECT NO. 2 1-WAY CLUTCH ASSEMBLY

  3. INSPECT REAR CLUTCH DISC

  4. INSPECT REVERSE CLUTCH HUB SUB-ASSEMBLY

  5. INSPECT FORWARD CLUTCH HUB SUB-ASSEMBLY

  6. INSPECT FORWARD MULTIPLE DISC CLUTCH DISC

  7. INSPECT FORWARD CLUTCH RETURN SPRING SUB-ASSEMBLY

  8. INSPECT DIRECT CLUTCH DISC

  9. INSPECT REVERSE CLUTCH RETURN SPRING SUB-ASSEMBLY

  10. INSPECT DIRECT CLUTCH RETURN SPRING SUB-ASSEMBLY

  11. INSPECT NO. 3 BRAKE DISC

  12. INSPECT NO. 3 BRAKE PISTON RETURN SPRING SUB-ASSEMBLY

  13. INSPECT FRONT PLANETARY GEAR ASSEMBLY

  14. INSPECT 1-WAY CLUTCH ASSEMBLY

  15. INSPECT NO. 1 BRAKE DISC

  16. INSPECT BRAKE PISTON RETURN SPRING SUB-ASSEMBLY

  17. INSPECT NO. 2 BRAKE DISC

  18. INSPECT NO. 2 BRAKE PISTON RETURN SPRING SUB-ASSEMBLY

  19. INSPECT CENTER PLANETARY GEAR ASSEMBLY

  20. INSPECT NO. 3 1-WAY CLUTCH ASSEMBLY

  21. INSPECT REAR PLANETARY RING GEAR FLANGE SUB-ASSEMBLY

  22. INSPECT INTERMEDIATE SHAFT

  23. INSPECT NO. 4 BRAKE DISC

  24. INSPECT REAR PLANETARY GEAR ASSEMBLY

  25. INSPECT 1ST AND REVERSE BRAKE RETURN SPRING SUB-ASSEMBLY

  26. INSPECT PACK CLEARANCE OF 1ST AND REVERSE BRAKE

  27. INSPECT PISTON STROKE OF NO. 1 BRAKE PISTON

  28. INSPECT PACK CLEARANCE OF DIRECT CLUTCH

  29. INSPECT PACK CLEARANCE OF REVERSE CLUTCH

  30. INSPECT PACK CLEARANCE OF FORWARD CLUTCH

  31. INSPECT INDIVIDUAL PISTON OPERATION

Automatic Transmission Unit -- Inspection



1. INSPECT AUTOMATIC TRANSMISSION OIL PAN SUB-ASSEMBLY
  1. Remove the magnets, and use them to collect steel particles.

  1. Carefully look at the foreign matter and particles in the pan and on the magnets to anticipate the type of wear you will find in the transmission.

    1. Steel (magnetic): bearing, gear and clutch plate wear
    2. Brass (non-magnetic): bushing wear


2. INSPECT NO. 2 1-WAY CLUTCH ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Hold the reverse clutch hub and turn the 1-way clutch assembly.

  1. Check that the 1-way clutch turns freely clockwise and locks when turned counterclockwise.

    Text in Illustration
    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
    Lock
    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
    Free


3. INSPECT REAR CLUTCH DISC


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  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) the grooves or printed numbers have even a little bit of damage.

    NOTICE:
    Before assembling new discs, soak them in ATF for at least 15 minutes.


4. INSPECT REVERSE CLUTCH HUB SUB-ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a dial indicator, measure the inside diameter of the reverse clutch hub bush.

    Standard inside diameter:
    35.812 to 35.837 mm (1.410 to 1.411 in.)
    Maximum inside diameter:
    35.887 mm (1.413 in.)
    1. If the inside diameter is more than the maximum, replace the reverse clutch hub.


5. INSPECT FORWARD CLUTCH HUB SUB-ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a dial indicator, measure the inside diameter of the forward clutch hub bush.

    Standard inside diameter:
    26.037 to 26.062 mm (1.025 to 1.026 in.)
    Maximum inside diameter:
    26.112 mm (1.028 in.)
    1. If the inside diameter is more than the maximum, replace the forward clutch hub.


6. INSPECT FORWARD MULTIPLE DISC CLUTCH DISC


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  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) the grooves or printed numbers have even a little bit of damage.

    NOTICE:
    Before assembling new discs, soak them in ATF for at least 15 minutes.


7. INSPECT FORWARD CLUTCH RETURN SPRING SUB-ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  1. Using a vernier caliper, measure the free length of the spring together with the spring seat.

    Standard free length:
    26.74 mm (1.05 in.)


8. INSPECT DIRECT CLUTCH DISC


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  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) the grooves or printed numbers have even a little bit of damage.

    NOTICE:
    Before assembling new discs, soak them in ATF for at least 15 minutes.


9. INSPECT REVERSE CLUTCH RETURN SPRING SUB-ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  1. Using a vernier caliper, measure the free length of the spring together with the spring seat.

    Standard free length:
    21.04 mm (0.828 in.)


10. INSPECT DIRECT CLUTCH RETURN SPRING SUB-ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  1. Using a vernier caliper, measure the free length of the spring together with the spring seat.

    Standard free length:
    19.51 mm (0.768 in.)


11. INSPECT NO. 3 BRAKE DISC


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  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) the grooves or printed numbers have even a little bit of damage.

    NOTICE:
    Before assembling new discs, soak them in ATF for at least 15 minutes.


12. INSPECT NO. 3 BRAKE PISTON RETURN SPRING SUB-ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  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.)


13. INSPECT FRONT PLANETARY GEAR ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a feeler gauge, measure the front planetary pinion gear thrust clearance.

    Standard clearance:
    0.2 to 0.6 mm (0.00787 to 0.0236 in.)
    Maximum clearance:
    0.65 mm (0.0256 in.)
    1. If the clearance is more than the maximum, replace the front planetary gear assembly.


    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a cylinder gauge, measure the inside diameter of the front planetary gear bush.

    Maximum inside diameter:
    57.48 mm (2.26 in.)
    1. If the inside diameter is more than the maximum, replace the front planetary gear.


14. INSPECT 1-WAY CLUTCH ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Install the 1-way clutch to the 1-way clutch inner race.

  1. Hold the 1-way clutch inner race and turn the 1-way clutch assembly. Check that the 1-way clutch turns freely counterclockwise and locks when turned clockwise.

    Text in Illustration
    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
    Lock
    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
    Free
  1. Remove the 1-way clutch from the 1-way clutch inner race.



15. INSPECT NO. 1 BRAKE DISC


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Replace all the 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) the grooves or printed numbers have even a little bit of damage.

    Text in Illustration
    *A
    for 1GR-FE
    *B
    for 1KD-FTV
    NOTICE:
    Before assembling new discs, soak them in ATF for at least 15 minutes.


16. INSPECT BRAKE PISTON RETURN SPRING SUB-ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  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.)


17. INSPECT NO. 2 BRAKE DISC


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Replace all the 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) the grooves or printed numbers have even a little bit of damage.

    Text in Illustration
    *A
    for 1GR-FE
    *B
    for 1KD-FTV
    NOTICE:
    Before assembling new discs, soak them in ATF for at least 15 minutes.


18. INSPECT NO. 2 BRAKE PISTON RETURN SPRING SUB-ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  1. Using a vernier caliper, measure the free length of the spring together with the spring seat.

    Standard free length:
    17.45 mm (0.687 in.)


19. INSPECT CENTER PLANETARY GEAR ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a feeler gauge, measure the center planetary pinion gear thrust clearance.

    Standard clearance:
    0.12 to 0.68 mm (0.00472 to 0.0268 in.)
    Maximum clearance:
    0.73 mm (0.0287 in.)
    1. If the clearance is more than the maximum, replace the center planetary gear assembly.


20. INSPECT NO. 3 1-WAY CLUTCH ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Hold the rear planetary ring gear flange and turn the 1-way clutch. Check that the 1-way clutch turns freely counterclockwise and locks when turned clockwise.

    Text in Illustration
    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
    Lock
    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
    Free


21. INSPECT REAR PLANETARY RING GEAR FLANGE SUB-ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a dial indicator, measure the inside diameter of the rear planetary ring gear bush.

    Standard inside diameter:
    32.176 to 32.201 (1.267 to 1.268 in.)
    Maximum inside diameter:
    32.251 mm (1.270 in.)
    1. If the inside diameter is more than the maximum, replace the rear planetary ring gear.


22. INSPECT INTERMEDIATE SHAFT


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a dial indicator, measure the intermediate shaft runout.

    Standard runout:
    0.03 mm (0.00118 in.)
    Maximum runout:
    0.08 mm (0.00315 in.)
    If the runout is more than the maximum, replace the intermediate shaft with a new one.


    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a micrometer, measure the diameter of the intermediate shaft at the positions shown in the diagram.

    Standard diameter:
    A, B:
    25.962 to 25.975 mm (1.022 to 1.023 in.)
    C, D:
    32.062 to 32.075 mm (1.262 to 1.263 in.)
    Minimum diameter:
    A, B:
    25.912 mm (1.02 in.)
    C, D:
    32.012 mm (1.26 in.)
    If the diameter is less than the minimum, replace the intermediate shaft with a new one.


23. INSPECT NO. 4 BRAKE DISC


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Replace all the 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) the grooves or printed numbers have even a little bit of damage.

    Text in Illustration
    *A
    for 1GR-FE
    *B
    for 1KD-FTV
    NOTICE:
    Before assembling new discs, soak them in ATF for at least 15 minutes.


24. INSPECT REAR PLANETARY GEAR ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  1. Using a feeler gauge, measure the rear planetary pinion gear thrust clearance.

    Standard clearance:
    0.2 to 0.6 mm (0.00787 to 0.0236 in.)
    Maximum clearance:
    0.65 mm (0.0256 in.)
    1. If the clearance is more than the maximum, replace the planetary gear assembly.


    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  1. Using a dial indicator, measure the inside diameter of the rear planetary gear bush.

    Maximum inside diameter:
    20.075 mm (0.790 in.)
    1. If the inside diameter is more than the maximum, replace the rear planetary gear assembly.


25. INSPECT 1ST AND REVERSE BRAKE RETURN SPRING SUB-ASSEMBLY


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
  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.)


26. INSPECT PACK CLEARANCE OF 1ST AND REVERSE BRAKE


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Make sure the 1st and reverse brake piston moves smoothly when applying and releasing compressed air into the transmission case.



27. INSPECT PISTON STROKE OF NO. 1 BRAKE PISTON


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Make sure the No. 1 brake piston moves smoothly when applying and releasing compressed air into the transmission case.



    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a feeler gauge, measure the B3 bearing pack clearance between the snap ring and flange.

    Standard piston stroke:
    0.42 to 0.72 mm (0.0165 to 0.0283 in.)
    If the piston stroke is outside the specification, parts may have been assembled incorrectly. Perform the reassembly again. If the piston stroke is still outside the specification, select another flange.
    HINT:
    There are 4 different thicknesses for the flange.


28. INSPECT PACK CLEARANCE OF DIRECT CLUTCH


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a dial indicator, measure the moving distance (distance A) of the clutch flange at both ends across a diameter while applying air to the oil hole as shown in the illustration, and calculate the average.

    Standard pack clearance for 1GR-FE:
    0.5 to 0.8 mm (0.0197 to 0.0315 in.)
    Standard pack clearance for 1KD-FTV:
    0.6 to 0.9 mm (0.0236 to 0.0354 in.)
    NOTICE:
    When measuring the moving distance, install a standard flange (thickness: 3.4 mm (0.134 in.)) to the position of the shaded area in the illustration.
    HINT:
    Flange moving distance A = 0.26 to 1.14 mm (0.0102 to 0.0449 in.)
    Pack clearance = Flange moving distance A - 0.05 mm (0.00197 in.)
    If the pack clearance is outside the standard, select and install a clutch flange that makes the pack clearance within the standard.
    Flange Thickness:
    Mark
    Thickness
    2
    2.95 to 3.05 mm (0.116 to 0.120 in.)
    3
    3.05 to 3.15 mm (0.120 to 0.124 in.)
    4
    3.15 to 3.25 mm (0.124 to 0.128 in.)
    5
    3.25 to 3.35 mm (0.128 to 0.132 in.)
    6
    3.35 to 3.45 mm (0.132 to 0.136 in.)
    7
    3.45 to 3.55 mm (0.136 to 0.140 in.)
    8
    3.55 to 3.65 mm (0.140 to 0.144 in.)
    9
    3.65 to 3.75 mm (0.144 to 0.148 in.)
    A
    3.75 to 3.85 mm (0.148 to 0.152 in.)


29. INSPECT PACK CLEARANCE OF REVERSE CLUTCH



Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection

  1. Using a dial indicator, measure the reverse clutch piston stroke (distance A) and the moving distance (distance B) of the reverse flange at both ends across a diameter while applying air (392 kPa (4.0 kgf/cm2, 57 psi)) to the oil hole as shown in the illustration, and calculate the average.

    Standard pack clearance:
    0.5 to 0.8 mm (0.0197 to 0.0315 in.)
    NOTICE:
    When measuring the moving distance, install a standard flange (thickness: 3.3 mm (0.130 in.)) to the position of the shaded area in the illustration.
    HINT:
    Piston stroke A = 1.05 to 2.15 mm (0.0413 to 0.0846 in.)
    Flange moving distance B = 0.72 to 1.08 mm (0.0283 to 0.0425 in.)
    Pack clearance = Piston stroke A - Flange moving distance B - 0.06 mm (0.00236 in.)
    If the pack clearance is outside the standard, select and install a clutch flange that makes the pack clearance within the standard.
    Flange Thickness:
    Mark
    Thickness
    0
    2.75 to 2.85 mm (0.108 to 0.112 in.)
    1
    2.85 to 2.95 mm (0.112 to 0.116 in.)
    2
    2.95 to 3.05 mm (0.116 to 0.120 in.)
    3
    3.05 to 3.15 mm (0.120 to 0.124 in.)
    4
    3.15 to 3.25 mm (0.124 to 0.128 in.)
    5
    3.25 to 3.35 mm (0.128 to 0.132 in.)
    6
    3.35 to 3.45 mm (0.132 to 0.136 in.)
    7
    3.45 to 3.55 mm (0.136 to 0.140 in.)
    8
    3.55 to 3.65 mm (0.140 to 0.144 in.)
    9
    3.65 to 3.75 mm (0.144 to 0.148 in.)
    A
    3.75 to 3.85 mm (0.148 to 0.152 in.)


30. INSPECT PACK CLEARANCE OF FORWARD CLUTCH


Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  1. Using a dial indicator, measure the moving distance (distance A) of the clutch flange at both ends across a diameter while applying air to the oil hole as shown in the illustration, and calculate the average.

    Standard pack clearance for 1GR-FE:
    0.6 to 0.9 mm (0.0236 to 0.0354 in.)
    Standard pack clearance for 1KD-FTV:
    0.8 to 1.0 mm (0.0315 to 0.0394 in.)
    NOTICE:
    When measuring the moving distance, install a standard flange (thickness: 3.4 mm (0.134 in.)) to the position of the shaded area in the illustration.
    HINT:
    Flange moving distance A = 0.26 to 1.36 mm (0.0102 to 0.0535 in.)
    Pack clearance = Flange moving distance A - 0.01 mm (0.000394 in.)
    If the pack clearance is outside the standard, select and install a clutch flange that makes the pack clearance within the standard.
    Flange Thickness:
    Mark
    Thickness
    0
    2.95 to 3.05 mm (0.116 to 0.120 in.)
    1
    3.05 to 3.15 mm (0.120 to 0.124 in.)
    2
    3.15 to 3.25 mm (0.124 to 0.128 in.)
    3
    3.25 to 3.35 mm (0.128 to 0.132 in.)
    4
    3.35 to 3.45 mm (0.132 to 0.136 in.)
    5
    3.45 to 3.55 mm (0.136 to 0.140 in.)
    6
    3.55 to 3.65 mm (0.140 to 0.144 in.)
    7
    3.65 to 3.75 mm (0.144 to 0.148 in.)
    8
    3.75 to 3.85 mm (0.148 to 0.152 in.)
    9
    3.85 to 3.95 mm (0.148 to 0.152 in.)
    A
    3.95 to 4.05 mm (0.152 to 0.159 in.)


31. INSPECT INDIVIDUAL PISTON OPERATION


    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe).Automatic Transmission Unit  Inspection
  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 with the accumulator piston holes indicated in the illustration.
    If there is no sound, disassemble and check the installation condition of the parts.
    1. No. 2 clutch (C2)
    2. No. 3 clutch (C3)
    3. No. 1 clutch (C1)
    4. No. 3 brake (B3)
    5. No. 1 brake (B1)
    6. No. 2 brake (B2)
    7. No. 4 brake (B4)