Shift pressure - RA27007229170X(27-9170)

WARNING: This page does not describe the selected car, but rather 42 other vehicles, including the 1999 Mercedes-Benz S600, 1999 Mercedes-Benz S500, 1999 Mercedes-Benz S420, 1999 Mercedes-Benz S320, and 1999 Mercedes-Benz CL600. However, it is still accessible from the selected car via links, so may be relevant.

The shift pressure influences the shift quality when clutches K1 and K2 and brake band B1 are engaged and disengaged.

The shift pressure acts in the spring chambers of dampers K1, K2 and in damper B1.

The shift pressure is derived from the working pressure and is controlled at the shift pressure control valve (47).

The shift pressure acts on the end face (c) and pushes the control valve (47) against the modulating pressure "M1" into the control position. This causes the working pressure inlet at the control edge (a) to be restricted and the zero discharge to be opened to reduce the pressure.

The level of the shift pressure is determined by the modulating pressure "M1" and by the force of the spring.

This means:

low modulating pressure =low shift pressure

high modulating pressure =high shift pressure

Fig 1: Identifying Shift Pressure Diagram

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.