Mercedes-Benz ML320. Manual — part 141

Fig. 17: Shift From 1 To 2, Function (Shift Phase)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

2001 Mercedes-Benz ML320

1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662

me

2001 Mercedes-Benz ML320

1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662

me

Fig. 18: Shift From 1 To 2, Function (Second Gear Engaged)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Aim

Engage front multiple-disc clutch (K1), disengage front multiple-disc brake (B1).

Operation

1st Gear Engaged See Fig. 16.

The end face of the 1-2/4-5 command valve (31a) is kept depressurized via the 1-2 and 4-5 shift solenoid valve
(Y3/6y3). Via the 1-2/4-5 holding pressure shift valve (28a), working pressure (p-A) is applied to the front
mutiple-disc clutch (K1) is depressurized.

Shift Phase

See Fig. 17

Via the 1-2 and 4-5 shift solenoid valve (Y3/6y3), the shift valve pressure (p-SV) is directed onto the end face
of the command valve 1-2/4-5 (31a). The 1-2/4-5 command valve (31a) is displaced and the shift pressure (p-S)
coming from the 1-2/4-5 shift pressure shift valve (29a) via the 1-2/4-5 command valve (31a) is directed to the
front multiple-disc clutch (K1). At the same time the front multiple-disc brake (B1) is subjected to overlap
pressure from the 1-2/4-5 overlap regulating valve (30a).

The B1 pressure acting on the end face of the 1-2/4-5 shift pressure shift valve (29a) is superseded by the
working pressure (p-A). The increasing shift pressure (p-S) at the front multiple-disc clutch (K1) acts on the
annular area of the 1-2/4-5 overlap regulating valve (30a). With an appropriate pressure level at the 1-2/4-5
holding pressure shift valve (28a) this valve switches over.

2nd Gear Engaged

See Fig. 18.

After the gear change is complete, the pressure on the end face of the 12-/4-5 command valve (31a) is reduced
via the 1-2 and 4-5 shift solenoid valve (Y3/6y3) and the command value is pushed back into its original
position. Via the 1-2/4-5 holding pressure shift valve (28a) working pressure (p-A) now reaches the front
multiple-disc clutch (K1) via the 1-2/4-5 command valve (31a).

The front multiple-disc brake (B1) is disengaged (depressurized). The spring in the 1-2/4-5 shift pressure shift
valve (29a) pushes this into its original position.

Continuation

Operating Pressure, Function

See OPERATING PRESSURE, FUNCTION.

Shift Pressure, Function

2001 Mercedes-Benz ML320

1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662

me

See SHIFT PRESSURE, FUNCTION.

Modulating Pressure, Function

See MODULATING PRESSURE, FUNCTION.

Shift Valve Pressure, Function

See SHIFT VALVE PRESSURE, FUNCTION.

Lubricating Pressure, Function

See LUBRICATING PRESSURE, FUNCTION.

Regulating Valve Pressure, Function

See REGULATING VALVE PRESSURE, FUNCTION.

AUTOMATIC TRANSMISSION, CONTENTS, FUNCTION DESCRIPTION

Automatic Transmission, Function

See AUTOMATIC TRANSMISSION, FUNCTION.

Automatic Transmission, Location Of Mechanical Parts

See AUTOMATIC TRANSMISSION, LOCATION OF MECHANICAL PARTS.

Automatic Transmission, Location Of Electric/Electronic Components

See AUTOMATIC TRANSMISSION, LOCATION OF ELECTRIC/ELECTRONIC
COMPONENTS.

Automatic Transmission, Location Of Hydraulic Components

See AUTOMATIC TRANSMISSION, POSITION OF HYDRAULIC COMPONENTS

Automatic Transmission, Location Of Components, Floor Shift

See AUTOMATIC TRANSMISSION, LOCATION OF COMPONENTS, FLOOR SHIFT.

Automatic Transmission, Selector Lever Positions

See AUTOMATIC TRANSMISSION, SELECTOR LEVER POSITIONS.

NOTE:

Transmission with touch shift.

2001 Mercedes-Benz ML320

1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662

me