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GF27.60-P-3024AHZ Working/Lubrication/Shift Pressure, Function



GF27.60-P-3024AHZ Working/lubrication/shift pressure, function
- Transmission 722.902/903/904/906/907 [model 164.1]
- Transmission 722.902/903/904 [model 164.8]
- Transmission 722.902/904/906/999 [model 251.1]


Function requirements for working/lubrication/shift pressure, general
^ Circuit 87 ON
^ Circuit 61 (engine running)

Working/lubrication/shift pressure, general
The oil pressures are separated into:
^ Working pressure
^ Lubricating pressure
^ Shift pressure

Working pressure
The oil pressure produced by the oil pump is converted into working pressure by the working pressure regulating valve. The level of working pressure depends on the position of the regulating valve and therefore on its geometry.

The position of the working pressure regulating valve is influenced by the working pressure control solenoid valve (VGS) (Y3/8y1) in a manner which is dependent on load and gear. All other pressures required for the transmission control are derived from the working pressure.

Lubricating pressure
Excess oil is diverted to the lubrication pressure regulating valve at the working pressure regulating valve and from there used in a regulated manner for lubricating and cooling the mechanical transmission parts and torque converter.

In addition the pressure in the torque converter is limited via the lubrication pressure.

Shift pressure
The shift pressure (pressure in the multi-disk clutch or in multi-disk brake) is derived from the working pressure.

The respective control solenoid valve influences the position of the associated regulating valve. In turn the position influences the pressure prevailing in the multi-disk brake or in multi-disk clutch. The pressure thus depends on the geometry of the respective regulating valve.