Working/Lubrication/Shift Pressure, Function - GF27.60-P-3024AHG
TRANSMISSION 722.9 in MODEL 463 as of model year 2013
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
- Lubrication 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 (Y3/8y1) depending on load and gear. All other pressures required for transmission control are derived from the working pressures.
The optimized working pressure reduction enables lower braking power and therefore reduces the fuel consumption.
Lubrication 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 by the level of lubrication pressure.
Shift pressure
The shift pressure (pressure in the multidisk clutch or in multidisk 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 multidisk brake or in multidisk clutch. The pressure thus depends on the geometry of the respective regulating valve.
The electric transmission oil pump (M42) ensures a continued supply of oil to the hydraulic system when the engine is switched off. This is actuated through the gear oil auxiliary pump control unit (N89).
| Overview of system components for automatic transmission (AT) | GF27.10-P-9992AHG |