Overdrive Brake Disassembly


  1. INSPECT PISTON OPERATION OF OVERDRIVE BRAKE

  2. REMOVE OVERDRIVE BRAKE RETURN SPRING

  3. INSPECT OVERDRIVE BRAKE RETURN SPRING

  4. REMOVE OVERDRIVE BRAKE PISTON

  5. REMOVE OVERDRIVE CLUTCH DRUM OIL SEAL RING

  6. INSPECT OVERDRIVE BRAKE CLUTCH DISC

Overdrive Brake -- Disassembly



1. INSPECT PISTON OPERATION OF OVERDRIVE BRAKE


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340E Automatic Transmission.Overdrive Brake.Overdrive Brake  Disassembly
  1. Place the overdrive support assembly onto the direct clutch assembly.



    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340E Automatic Transmission.Overdrive Brake.Overdrive Brake  Disassembly
  1. Apply compressed air (392 kPa (4 kgf/cm2, 57 psi)) into the oil passage, and check that the overdrive brake piston moves smoothly.



2. REMOVE OVERDRIVE BRAKE RETURN SPRING


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340E Automatic Transmission.Overdrive Brake.Overdrive Brake  Disassembly
  1. Place SST on the retainer spring, and compress the return spring with a press.

    SST
    09350-30020(09350-07030)
  1. Using a screwdriver, pry out the snap ring.

  1. Remove the brake return spring.



3. INSPECT OVERDRIVE BRAKE RETURN SPRING


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340E Automatic Transmission.Overdrive Brake.Overdrive Brake  Disassembly
  1. Using a vernier caliper, measure the free length of the spring together with the spring seat.

    Standard free length:
    17.03 mm (0.671 in.)
    If the length is not as specified, replace the spring.


4. REMOVE OVERDRIVE BRAKE PISTON


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340E Automatic Transmission.Overdrive Brake.Overdrive Brake  Disassembly
  1. Place the overdrive support onto the direct clutch assembly.

  1. Hold the overdrive brake piston so that it does not slant, and apply compressed air (392 kPa (4 kgf/cm2, 57 psi)) into the passage to remove the overdrive brake piston.

  1. Remove the overdrive brake piston.



    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340E Automatic Transmission.Overdrive Brake.Overdrive Brake  Disassembly
  1. Remove the 2 O-rings.



5. REMOVE OVERDRIVE CLUTCH DRUM OIL SEAL RING


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340E Automatic Transmission.Overdrive Brake.Overdrive Brake  Disassembly
  1. Remove the 2 oil seal rings.



    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340E Automatic Transmission.Overdrive Brake.Overdrive Brake  Disassembly
  1. Remove clutch drum thrust washer from overdrive support.



6. INSPECT OVERDRIVE BRAKE CLUTCH DISC


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.A340E Automatic Transmission.Overdrive Brake.Overdrive Brake  Disassembly
  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.

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