
Shifting "N" To "D" (1st Gear), Function
See SHIFTING N TO D (1ST GEAR), FUNCTION
.
Function Of Shift From 1 To 2
See SHIFT FROM 1 TO 2, FUNCTION
.
Limp-home Mode, Function
See LIMP
-HOME MODE, FUNCTION.
Operating Pressure, Function
See OPERATING PRESSURE, FUNCTION
.
Lubricating Pressure, Function
See LUBRICATING PRESSURE, FUNCTION
.
Shift Pressure, Function
See SHIFT PRESSURE, FUNCTION
.
Modulating Pressure, Function
See MODULATING PRESSURE, FUNCTION
.
Shift Valve Pressure, Function
See SHIFT VALVE PRESSURE, FUNCTION
.
Manual Drive Mode Selection, Function
See MANUAL DRIVE MODE SELECTION, FUNCTION
.
Oil Level Control, Function
See OIL LEVEL CONTROL, FUNCTION
.
Torque Converter Lockup Clutch Control, Function
See FUNCTION OF TORQUE CONVERTER LOCKUP CLUTCH CONTROL
.
Torque Converter Lockup Clutch Control Pressure, Function
See TORQUE CONVERTER LOCKUP CLUTCH CONTROL PRESSURE, FUNCTION
.
2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
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Saturday, October 02, 2010 3:15:25 PMPage 22 © 2006 Mitchell Repair Information Company, LLC.

Limp-Home Mode, Function
See LIMP
-HOME MODE, FUNCTION.
Operating Pressure, Function
See OPERATING PRESSURE, FUNCTION
.
Lubricating Pressure, Function
See LUBRICATING PRESSURE, FUNCTION
.
Shift Pressure, Function
See SHIFT PRESSURE, FUNCTION
.
Modulating Pressure, Function
See MODULATING PRESSURE, FUNCTION
.
Regulating Valve Pressure, Function
See REGULATING VALVE PRESSURE, FUNCTION
.
Shift Valve Pressure, Function
See SHIFT VALVE PRESSURE, FUNCTION
.
Hydropneumatic Transmission Control, Function
See HYDROPNEUMATIC TRANSMISSION CONTROL, FUNCTION
.
Manual Drive Mode Selection, Function
See MANUAL DRIVE MODE SELECTION, FUNCTION
.
Oil Level Control
See OIL LEVEL CONTROL, FUNCTION
.
Function Of Torque Converter Lockup Clutch Control
See FUNCTION OF TORQUE CONVERTER LOCKUP CLUTCH CONTROL
.
Torque Converter Lockup Clutch Control Pressure, Function
See TORQUE CONVERTER LOCKUP CLUTCH CONTROL PRESSURE, FUNCTION
2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
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Saturday, October 02, 2010 3:15:25 PMPage 31 © 2006 Mitchell Repair Information Company, LLC.

Shift-Lock, Function
See SHIFT
-LOCK FUNCTION.
Park Pawl Interlock, Function
See PARK PAWL INTERLOCK, FUNCTION
.
Steering Lock Interlock, Function
See STEERING LOCK INTERLOCK, FUNCTION
.
Survey Of System Components, Automatic Transmission, Location/Task/Design/Function
See SURVEY OF SYSTEM COMPONENTS, AUTOMATIC TRANSMISSION,
LOCATION/TASK/DESIGN/FUNCTION.
Automatic Transmission, Function
Automatic transmission 722.6 is an electronically controlled 5-speed transmission with a lockup clutch in the
torque converter.
The ratios for the gear stages are achieved by three planetary gear sets. The 5th gear is designed with a step-up
ratio as an overdrive.
Shifting is initiated electronically. The gears are shifted by the corresponding combination of three
hydraulically actuated multi-disc clutches and two mechanical freewheels.
Basically automatic transmission 722.6 with electronic control offers the following advantages:
Reduced Fuel Consumption
Improved Shift Comfort
More Favorable Gear Steps As A Result Of 5 Gears
Enhanced Life And Reliability
Reduced Servicing Costs
The electrohydraulic control unit is bolted onto the bottom of the transmission housing. The end of the
transmission is formed by an oil pan made of sheet steel.
The oil pressure for the converter lockup clutch and center multiple-disc clutch is supplied via holes in the input
shaft. The oil pressure to the rear mulitiple-disc clutch is routed through the output shaft. The lubricating oil is
supplied and distributed by additional bore holes in both shafts. All bearing points of the gear sets as well as
freewheels and shift elements are supplied with lubricatin
g oil. NOTE: Transmission Without Touch Shift 722.6 In Model 163.
2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
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Saturday, October 02, 2010 3:15:25 PMPage 32 © 2006 Mitchell Repair Information Company, LLC.

The parking lock gear and drive flange are connected to the output shaft by gearing.
Freewheels F1 and F2 optimize shifting. The front freewheel (F1) rests against the stator shaft extension on the
transmission side and connects the sun gear of the front planetary gear set tot the transmission housing in the
locking direction.
The torque converter housing and transmission housing are made of a metal alloy. They are bolted together and
centered via the outer multiple-disc carrier of the multiple-disc brake B1. A coated intermediate panel seals the
two components.
The oil pump and outer multiple-disc carrier of the front multiple-disc brake are bolted to the converter housing.
The mechanical part consists of the propeller shaft, output shaft, a sun gear shaft and three planetary gearsets
which are coupled together.
In transmissions for powerful engines, the planetary gearsets have 4 planetary gears, while for less powerful
engines the front and rear planetary gear system has three planetary gear wheels. The stator shaft is pressed into
this and is secured against turning by a spline.
The rear freewheel (F2) connects the sun gear of the center planetary gear set to the sun gear of the rear
planetary gearset in the locking direction.
The electrohydraulic control unit consists of the shift plate made of light alloy for hydraulic control and an
electronic control unit.
The electrical control unit consists of a supporting body made of plastic in which the electrical components are
combined. The shell is screwed tot he shift plate. Conductor tracks which are integrated into the shell, connect
the electric components to a plug connector. This 13-pin plug connector forms the connection with the vehicle-
side wiring harness and with the ETC 5 (Electronic Transmission Control) control module (N15/5) via a
bayonet lock.
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
.
2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
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Saturday, October 02, 2010 3:15:26 PMPage 33 © 2006 Mitchell Repair Information Company, LLC.

Floor Shift, Location/Task/Design/Function
See FLOOR SHIFT, LOCATION/TASK/DESIGN/FUNCTION
.
Location/Task/Design/Function Of Oil Pump
See LOCATION/TASK/DESIGN/FUNCTION OF OIL PUMP
.
Parking Lock, Location/Task/Design/Function
See PARK PAWL, LOCATION/TASK/DESIGN/FUNCTION
.
Planetary Gear Set, Location/Task/Design/Function
See PLANETARY GEAR SET, LOCATION/TASK/DESIGN/FUNCTION
.
Position Sensor, Location/Task/Function
See POSITION SENSOR, LOCATION/TASK/FUNCTION
.
Location/Task/Design/Function Of PWM Solenoid Valve, Torque Converter Lockup Clutch
See LOCATION/TASK/DESIGN/FUNCTION OF PWM SOLENOID VALVE, TORQUE
CONVERTER LOCKUP CLUTCH.
Modulating Pressure Regulating Solenoid Valve, Location/Task/Design/Function
See MODULATING PRESSURE REGULATING SOLENOID VALVE,
LOCATION/TASK/DESIGN/FUNCTION.
Shift Pressure Regulating Solenoid Valve, Location/Task/Design/Function
See SHIFT PRESSURE REGULATING SOLENOID VALVE,
LOCATION/TASK/DESIGN/FUNCTION.
Working Pressure Regulating Valve, Location/Task/Function
See WORKING PRESSURE REGULATING VALVE, LOCATION/TASK/FUNCTION
.
Regulating Valve Pressure Regulating Valve
See REGULATING VALVE PRESSURE REGULATING VALVE,
LOCATION/TASK/FUNCTION.
Shift Pressure Regulating Valve, Location/Task/Function
See SHIFT PRESSURE REGULATING VALVE, LOCATION/TASK/FUNCTION
.
2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
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Saturday, October 02, 2010 3:15:26 PMPage 43 © 2006 Mitchell Repair Information Company, LLC.

See MULTIPLE
-DISC BRAKE, LOCATION/TASK/DESIGN/FUNCTION.
Multi-Plate Clutch, Location/Task/Design/Function
See MULTI
-PLATE CLUTCH, LOCATION/TASK/DESIGN/FUNCTION.
Upshift/Downshift Solenoid Valve, Location/Task/Design/Function
See UPSHIFT/DOWNSHIFT SOLENOID VALVE, LOCATION/TASK/DESIGN/FUNCTION
.
Floor Shift, Location/Task/Design/Function
See FLOOR SHIFT, LOCATION/TASK/DESIGN/FUNCTION
.
Location/Task/Design/Function Of Oil Pump
See LOCATION/TASK/DESIGN/FUNCTION OF OIL PUMP
.
Parking Lock, Location/Task/Design/Function
See PARK PAWL, LOCATION/TASK/DESIGN/FUNCTION
.
Planetary Gear Set, Location/Task/Design/Function
See PLANETARY GEAR SET, LOCATION/TASK/DESIGN/FUNCTION
.
Position Indicator, Location/Task/Design/Function
See POSITION DISPLAY, LOCATION TASK
.
Location/Task/Design/Function Of PWM Solenoid Valve, Torque converter Lockup Clutch
See LOCATION/TASK/DESIGN/FUNCTION OF PWM SOLENOID VALVE, TORQUE
CONVERTER LOCKUP CLUTCH.
Modulating Pressure Regulating Solenoid Valve, Location/Task/Design/Function
See MODULATING PRESSURE REGULATING SOLENOID VALVE,
LOCATION/TASK/DESIGN/FUNCTION.
Shift Pressure Regulating Solenoid Valve, Location/Task/Design/Function
See SHIFT PRESSURE REGULATING SOLENOID VALVE,
LOCATION/TASK/DESIGN/FUNCTION.
Working Pressure Regulating Valve, Location/Task/Design/Function
2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
me
Saturday, October 02, 2010 3:15:26 PMPage 56 © 2006 Mitchell Repair Information Company, LLC.

vehicle is stationary and the engine is idling, boosts the engine torque and provides infinitely variable
engine speed and torque matching when moving off.
Torque Converter, Design
The impeller (P) is connected to the engine, the turbine wheel (T) is connected to the transmission input
shaft.
The stator (L) is connected to the transmission housing via a freewheel and the stator shaft (8).
Torque Converter, Function
See TORQUE CONVERTER, FUNCTION
.
Torque Converter, Function
Due to the effect of centrifugal force, the blades of the impeller (P) pump the oil outwards to the turbine wheel
(T), causing it to rotate. See Fig. 31
. The turbine wheel blades direct the oil onto the blades of the stator, which
in turn push the oil back to the impeller (P) (arrow). This diversion at the stator (L), which is supported against
the transmission housing via the freewheel, produces and increase in torque. At the maximum speed difference
between the impeller and the turbine wheel (T), the torque conversion achieves its maximum value at a factor of
1.8 to 2.0, dropping to a torque ratio of 1:1 as the speeds converge. From this operating state onwards, also
referred to as the coupling point, the stator (l) rotates with the impeller (P) and the turbine wheel (T).
Efficiencies of up to approximately 98% are achieved in the coupling range.
The oil in the torque converter is constantly being replaced so that the heat produced in the operating phase can
be dissipated via the transmission oil cooler.
2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
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Saturday, October 02, 2010 3:15:26 PMPage 63 © 2006 Mitchell Repair Information Company, LLC.

Fig. 35: Electronic Control Module, Design
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Structure
The electrical control unit (Y3/6) consists of a supporting body made from plastic, in which the electrical
components, RPM sensors 2 and 3 (Y3/6n2, Y3/6n3), the regulating solenoid valves (Y3/6y1, Y3/6y2), the shift
solenoid valves (Y3/6y6), the starter lockout contact (Y3/6s1) and transmission oil temperature sensor (Y3/6b1)
are combined. See Fig. 35
. Conductor tracks integrated into the shell connect the electric components to a plug
connection (11).
2001 Mercedes-Benz ML320
1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662
me
Saturday, October 02, 2010 3:15:26 PMPage 71 © 2006 Mitchell Repair Information Company, LLC.