SsangYong Stavic / SsangYong Rodius (2005 year). Manual - part 301

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TORQUE CONVERTER

Function (4WD)

Torque converter is installed between engine and automatic transmission. It consists of pump impeller, turbine and
stator. The pump impeller is welded at converter housing and the converter housing is bolted at the drive plate.

The torque converter converts the mechanical energy from engine to hydraulic energy, and the turbine connected to
transmission input shaft converts this hydraulic energy to mechanical energy again. The stator between pump and
turbine increases the output torque from turbine by converting the flowing direction.

The stator has a torque converter area that changes the flowing direction and a fluid coupling area where the stator
rotates. And, the lockup clutch integrated in torque converter prevents the power from losing and reduces fuel consumption.

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• Use special tools when removing and installing torque

converter.

Specified installation height (A)

below 6.5 mm

• The distance between the upper end of torque converter

and the mating surface of automatic transmission housing
should be within specified value as follows:

• Place the automatic transmission upright as shown in

figure and install the torque converter by rotating the torque
converter. When installing from sideway, the torque
converter sealing ring may be damaged by driving flange
which could cause oil leaks.

 [Notice]

Place the automatic transmission upright when removing
and installing torque converter.

If not, the oil seal may be damaged when servicing the torque
converter.

* Torque converter

P/NO

A210 250 05 02

Diameter

270 mm

Clutch disk

2 EA

Engine

E23/E28/E32/D27DT

Installation and Inspection

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LOCKUP CLUTCH

Lockup clutch consists of multiple disc clutches as shown
in the figure and is activated in 3th, 4th and 5th gears. The
aim of using torque converter lockup clutch is to reduce
the fuel consumption and exhaust gas emissions of the
vehicle by reducing torque converter slip. This stands in
contradiction to the ride comfort demands made on the
drive train with regard to its vibration behaviors. The task of
the electronic transmission control is therefore to close
the clutch in all driving situations relevant to fuel
consumption, if possible, and ensure that the engine vi-
brations are isolated from the drive train.

The characteristic curves shown in the diagram illustrate
the different operating states of the torque converter lockup
clutch in relation to the accelerator pedal position and the
transmission output speed, plotted for one transmission
gear.

• Variables influencing the states of the torque converter

lockup clutch:

1. Accelerator pedal movement
2. Uphill and downhill gradients
3. Transmission shift functions
4. Transmission oil temperature
5. Load conditions
6. Engine control influences

1. Impeller wheel

2. Turbine wheel

3. Stator wheel

4. Stator shaft

5. Multiple disc clutch drum

6. Multiple disc clutch hub

7. Converter cover

8. One-way clutch

9. Input shaft

10. Multiple disc clutch pack

11. Piston

A : Closed (lockup clutch activates)

B : Slipping

C : Open (lockup clutch deactivates)

n : Transmission output speed

d : Accelerator pedal position

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Lockup clutch regulating valve controls the lockup clutch in torque converter and distributes the lubricating oil to the
friction parts. TCU generates the lockup clutch control pressure by duty controlling the lockup solenoid valve, and this
pressure is applied to the lockup clutch regulating valve to engage, disengage and slip the lockup clutch. When the
lockup clutch control pressure is increased, the lockup clutch regulating valve moves up and the working pressure is
applied to lockup clutch. In its regulating position (slipping, torque converter lockup clutch pressurized), a reduced
volume of lubricating oil flows through the annular passage bypassing the torque converter and passing direct through
the oil cooler into the transmission. The rest of the lubricating oil is directed via the throttle “a” into the torque converter
in order to cool the torque converter lockup clutch.

Lockup Clutch Regulating Valve

Lockup clutch

Torque converter

output

Torque converter

input

Transmission

lubrication points

Oil cooler

Oil sump

drain

Working
pressure

Oil sump drain

Lubrication pressure

Oil sump drain

Torque converter lockup

solenoid valve

Shift valve

pressure