- Transmission selector and pressure control valve
- Torque converter outlet relief valve
- Lockup clutch solenoid valve
Converter Inlet Ratio Spool
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| Illustration 1 | g00485025 |
(1) Transmission selector and pressure control valve (2) Converter inlet ratio spool (3) Slug | |
The converter inlet ratio spool (2) is located in transmission selector and pressure control valve (1). The converter inlet ratio spool controls the maximum pressure that is allowed to the torque converter. Converter inlet ratio spool (2) limits the maximum pressure to the torque converter to 950 ± 55 kPa (138 ± 8 psi). Excess pressurized oil is directed to the transmission case.
Torque Converter Outlet Relief Valve
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| Illustration 2 | g00699234 |
The torque converter outlet relief valve is mounted to the back side of the torque converter. | |
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| Illustration 3 | g00485031 |
Torque Converter Outlet Relief Valve (4) Shims (5) Inlet passage from the torque converter (6) Valve spool for outlet relief valve (7) Outlet passage to the oil cooler | |
The torque converter outlet relief valve controls the maximum pressure of the oil inside the torque converter. Oil enters the torque converter outlet relief valve through passage (5) from the torque converter. The oil flows past spool (6) and out passage (7) to the transmission oil cooler. From the oil cooler, the oil flows through the transmission lube system to the sump. The torque converter outlet relief valve limits the pressure in the torque converter to 414 ± 34 kPa (60 ± 5 psi).
Modulating Valve (Torque Converter Lockup Clutch)
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| Illustration 4 | g00485032 |
The modulating valve for the torque converter lockup clutch is mounted on the top rear side of the torque converter. | |
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| Illustration 5 | g00485033 |
Modulating Valve (Torque Converter Lockup Clutch) (8) Pressure port (9) Drain (10) Lockup clutch port (11) Supply | |
The modulating valve controls the operation of the lockup clutch for the torque converter. Oil enters the valve through supply port (11) from the power train oil filter. The valve will then fill the lockup clutch. The valve then modulates the pressure in the lockup clutch. The valve maintains a pressure which is determined by the amount of current in the solenoid. The transmission electronic control module (ECM) determines the amount of current to supply to the lockup clutch valve. The amount of current is based on the response of the machine that is measured by the transmission output speed sensor and the pressure sensor for the lockup clutch.
The lockup clutch pressure can be measured at pressure port (8). The pressure should be approximately 1930 kPa (280 psi) in direct drive.
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| Illustration 6 | g00699237 |
The lockup clutch pressure sensor is mounted to the top of the torque converter. | |
The lockup clutch pressure sensor calibrates the lockup clutch solenoid so that the lockup clutch pressure is maintained.