Automatic Transmission System (For 1Gr-Fe) Hydraulic Test

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

  1. PERFORM HYDRAULIC TEST

Automatic Transmission System (For 1Gr-Fe) -- Hydraulic Test



PERFORM HYDRAULIC TEST


  1. Measure the line pressure.

    CAUTION:
    The line pressure test should always be carried out in pairs. One technician should observe the conditions of the wheels and wheel stoppers from outside the vehicle while the other is performing the test.
    NOTICE:
    1. Perform the test while the ATF (Automatic Transmission Fluid) temperature is 50 to 80°C (122 to 176°F).
    2. Be careful to prevent SST hose from interfering with the exhaust pipe.
    3. This check must be conducted after checking and adjusting the engine.
    4. Perform the test with the A/C off.
    5. When conducting the stall test, do not continue for more than 5 seconds.

    1. Warm up the ATF (Automatic Transmission Fluid).

    2. Turn the ignition switch off.

    3. Lift the vehicle up.



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

    4. Remove the test plug from the transmission case and connect SST.

      SST
      09992-00095(09992-00231,09992-00271)

    5. Lower the vehicle.

    6. Fully apply the parking brake and chock the 4 wheels.

    7. Start the engine and check the idling speed.

    8. Keep your left foot pressed firmly on the brake pedal and move the shift lever to D.

    9. Fully depress the accelerator pedal with your right foot. Quickly read the highest line pressure when the engine speed reaches stall speed.

    10. In the same manner, perform the test with the shift lever in R.

      Specified Line Pressure
      Condition
      		D Position
      		R Position
      Stall test
      		1350 to 1500 kPa
      (13.8 to 15.3 kgf/cm2, 196 to 218 psi)
      		1250 to 1550 kPa
      (12.7 to 15.8 kgf/cm2, 181 to 225 psi)

      Evaluation
      Problem
      		Possible Cause
      Measured values at all positions are higher than specified pressure
      1. Shift solenoid valve SLT defective
      2. Regulator valve defective
      Measured values at all positions are lower than specified pressure
      1. Shift solenoid valve SLT defective
      2. Regulator valve defective
      3. Oil pump defective
      Pressure is low in D only
      1. D position circuit fluid leak
      2. Clutch No. 1 (C1) defective
      Pressure is low in R only
      1. R position circuit fluid leak
      2. Clutch No. 3 (C3) defective
      3. Brake No. 4 (B4) defective