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




GF27.60-P-3024AHL Working/Lubrication/Shift Pressure, Function
- TRANSMISSION 722.9 (except 722.930 /931) in MODEL 212

Function requirements for working/lubrication/shift pressure general

^ Circuit 87 ON
^ Circuit 61 (engine running)

Working/lubrication/shift pressure in 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 (Y3/8y1) depending on load and gear. All other pressures required for the transmission control are derived from the working pressure.

Production breakpoints for implementation of fuel-efficient and comfort-enhancing measures on the automatic transmission
- Model 212.0/2 with engine 272 and 273 from 07/2010
- Model 212.0/2 with engine 276 and 278 from 06/2011
- Model 212.0/2 with engine 271.8 from 03/2011
- Model 212.0/2 with engine 642.8 from 07/2010
- Model 212.0/2 with engine 651.9 as of 12/2010

The optimized working-pressure reduction for the new generation of automatic transmissions enables lower braking power and therefore reduces the fuel consumption.

Lubricating pressure

At the working pressure regulating valve excess oil is diverted to the lubrication pressure regulating valve and from there used in a regulated manner for lubrication and cooling of mechanical transmission parts and the 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.