SsangYong Actyon Sports II. Manual — part 115

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3680-01

1. OVERVIEW

The six speed automatic (M78) transmission is

available in two variants: four wheel drive and

two wheel drive.

The transmission has the following features:

Six Forward Speeds

One reverse gear

A torque converter with an integral converter lock-up clutch

Electronic shift and pressure controls

A single planetary gear-set

A double planetary gear-set

Two hydraulically controlled brake bands

Three multi-plate clutches

All hydraulic functions are directed by electronic solenoids to control:

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Engagement feel

Shift feel

Shift scheduling

Modulated torque converter clutch applications

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The transmission contains fully synthetic automatic transmission fluid (ATF) and is filled for life; therefore

it does not require periodic servicing.

Engine power reaches the transmission via a torque converter with integral converter lock-up clutch.

The six forward gears and one reverse gear are obtained from a single planetary set, followed by a

double planetary set. This type of gear-set arrangement is commonly known as Lepelletier type gear-set.

The automatic transmission is electronically controlled. The control system is comprised of the following

elements:

External transmission control unit (TCU)

Internal embedded memory module (EMM)

Input and output speed sensors

Valve body unit comprised of four on/off solenoid valves and six variable bleed solenoids

Torque converter

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2. FEATURES

Early Downshifts with Hard Braking and Skip Shifts

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When heavy braking is detected, the transmission downshifts early and skips gears to provide increased

engine braking to provide gear selection for tip-in.

Gear Hold on Uphill/Downhill

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If the accelerator pedal is released when travelling uphill, upshifts are prevented to reduce busyness on

grades. If the accelerator pedal is released when travelling downhill, upshifts are prevented to enhance

engine braking.

Soft Engagement when Shifting to “D” and “R” Position

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A soft engagement feature avoids harsh take up of drive when selecting Drive or Reverse. This is

achieved by limiting engine speed and engine torque which results in a rapid, but progressive

engagement of either Drive or Reverse when moving from the Park or Neutral positions. There is no

drive engagement prevention strategy implemented on the transmission system as there is sufficient

engine strategy to protect the system. However, reverse gear engagement is prevented until engine

speed is less than 1400 rpm and the accelerator pedal position is less than 12% and vehicle speed is

less than 10 km/h.

Converter Clutch Lock-Up In All Gears

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The transmission features converter clutch lock-up in all gears. This feature provides improved fuel

economy and vehicle performance. It also improves transmission cooling efficiency when towing heavy

loads at low speeds, e.g. in city driving or hill terrain.

Embeded Memory Module (EMM)

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The embedded memory module (EMM) is

matched to the transmission's valve bodies

during transmission assembly to ensure refined

shift quality. The EMM is integrated into the input

speed sensor which is mounted on the valve

body in the transmission. The EMM is used to

store data such as valve body calibration data

and valve body serial number. Upon installation,

the TCU will download the data from the EMM

and utilise this data in the operation of the

transmission.

1) Features

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3680-01

2) Cooling System

The transmission cooling system ensures rapid warm-up and constant operating temperature resulting

in reduced fuel consumption and refined shift quality.

It also includes a cooler by-pass within the hydraulic system to allow sufficient cooling and lubrication to

the transmission drivetrain in the event of a blockage in the transmission cooler.

Gear Shift

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Coastdown

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Torque Demand

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Transmission gear change is controlled by the TCU. The TCU receives inputs from various engine and

vehicle sensors to select shift schedules and to control the shift feel and torque converter clutch (TCC)

operation at each gear change

Coastdown downshifts occur at 0% accelerator pedal when the vehicle is coasting down to a stop. To

reduce the shift shock and to improve the shift feeling during downshift, TCU electronically controls the

transmission.

Torque demand downshifts occur (automatically) when the driver demand for torque is greater than the

engine can provide at that gear ratio. If applied, the transmission will disengage the TCC to provide

added acceleration.

3) Shift Strategy

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3. MODE DESCRIPTIONS

1) Functions

Tip Switch in “M” Position (Manual Gear

Shift) (5)

The shiftable gear can be adjusted by

moving this switch to forward and rearward
when the gear select lever is in “M”

position.

5.

Shift Lock Release Button Hole when Locked in the "P" Position (1)

If you cannot move the gear select lever from the "P" position, try to move the lever while

pushing down here with a sharp object such as a ballpoint pen. For your safety, turn off the

engine and depress the brake pedal before the attempt.

1.

Gear Position (4)

P :

R :

N :

D :

4.

Mode Switch (3)

W :

S :

3.

Selection of Manual/Automatic Shift Function (M↔D) (2)

D :

M :

2.

Automatic shift according to the driving condition

Manual shift

Winter mode (Start off the vehicle in 2nd gear)

Standard mode (Use the standard mode in normal driving conditions.)

Park

Reverse

Neutral

Drive