Subaru Forester

1997-2005 of release

Repair and car operation

Subaru Forester
+ Cars Subaru Forester
+ The maintenance instruction
+ Routine maintenance
+ The engine
+ Systems of cooling, heating
+ The power supply system and release
+ Engine electric equipment
+ Control systems of the engine
- Gear change box
   + 5-step manual box of a gear change (РКПП)
   - 4-step automatic transmission (АТ)
      The general information and functioning principle
      Problem diagnostics АТ - the general information
      Adjustments АТ
      Electrohydraulic control system АТ, - the general information, appointment of basic elements
      Self-diagnostics system, reading of codes of malfunctions
      Removal and installation АТ
+ Coupling, трансмиссионная a line
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment


4-step automatic transmission (АТ)

The general information and functioning principle

The general data

Design АТ

1  —  Blocking муфта the hydrotransformer
2  — the  Hydrotransformer
3  — the  Leading shaft
4  — the  Shaft of a drive of the pump
5  —  Carter of the transformer
6  — the  Pump
7  —  Carter of the pump
8  —  Carter of a transmission
9  —  Mufta of inclusion of a reverse gear
10  — the  Tape brake
11  —  Mufta of inclusion of 4th transfer
12  — a  Forward planetary number
13  — a  Back planetary number
14  —  Mufta of a forward course
15  —  Mufta of a free wheeling of switching from 3rd transfer on 4th
16  —  Mufta of maintenance of a mode of braking by the engine

17  —  Mufta of inclusion of the first and back transfers
18  —  муфта a free wheeling of switching from 1st transfer on 2nd
19  — the  Intermediate shaft
20  — the  Gear wheel of intermediate transfer
21  —  Mufta of management of a back drive
22  — the  Shaft of a drive of the back bridge
24  — the  Gear wheel of intermediate transfer
25  — the  Gear wheel of blocking of a target shaft
26  —  Klapannaja assemblage
27  — the  Pallet картера
28  — the  Leading gear wheel of the main transfer
29  — the  Conducted gear wheel of the main transfer
30  — the  Pump wheel of the transformer
31  — the  transformer Reactor
32  — the  Turbine wheel of the transformer

The given Part of the Head a gear change Box is devoted automatic transmission (АТ). The information on РКПП is resulted in the Part a 5-step manual box of a gear change (РКПП) the present Chapter.

For a complete set of models considered in the present Management, are used АТ with an electronic control system.

System problems include exact management of switching of high-speed modes, decision-making on necessity of use of a mode of braking by the engine and hydrotransformer blocking and so forth As the initial information at decision-making by the management module (TCM) data arriving from corresponding gauges on position throttle заслонки, speeds of movement of a vehicle, engine turns, position of the lever of selector AT, etc. are used

Besides, the control system automatically defines a demanded mode of functioning of the engine. Depending on movement parametres such modes of functioning of the engine as "normal" (the most economic mode) and "forced" when selection of full capacity developed by the unit is provided that happens can get out it is necessary, for example, at overtakings or long lifting uphill.

The transmission consisting of two simple planetary numbers with одновенцовыми by satellites, provides possibility of reception of optimum parametres of dynamics of movement of the car.

The box provides four transfers of a forward course and one - back.

For management of a transmission two are used муфты a free wheeling and four hydroaccumulators providing smoothness of a gear change and blocking of the hydrotransformer.

For decrease in level transferred to a body of the car of vibrations АТ it is equipped special демпферной by system.

In TCM the self-diagnostics block is included that appreciably raises reliability of functioning of transmission and facilitates search of causes of failures.

In view of complexity of design АТ, absence on free sale of replaceable internal components, and also necessity of use of the special equipment, composers of the present Management do not recommend to owners of cars to carry out transmission major repairs by own forces. In the present Chapter procedures of diagnostics of general refusals АТ, its routine maintenance, the basic adjustments, removal and installation are considered only.

Sometimes, in case of serious breakage to replace transmission more reasonably and easier, than to waste time and means for restoration of the failed assemblage. Without dependence from the chosen way of introduction refused АТ in action, independent performance of its removal and installation expenses (before make sure that transmission really requires regenerative repair) will help to cut down substantially.

Towage of the car with refused АТ should be made with a speed not above 50 km/h (30 miles/ch) and on distance no more than 80 km (50 miles)!

Features of a control system

The electronic control system of all all-wheel drive models Subaru is developed on the basis of a control system of front-wheel models. The hydraulic part of a control system in addition includes the electromagnetic valve and муфту managements of a drive of back wheels. On the basis of the analysis of data TCM arriving from various information gauges defines optimum size of the twisting moment transferred to back wheels of the car and realises it by means of the electromagnetic valve at the expense of management of pressure in бустере муфты managements of a back drive.

The electronic control system precisely sets modes of functioning of the managing director муфты a back drive that is especially effective at car operation in heavy road conditions at movement on small speeds when special value gets smoothness of change of traction effort developed by driving wheels.

For the models equipped ABS, thanks to муфты managements of a back drive efficiency of braking of a vehicle raises.

In comparison with РКПП the general controllability of the car that is reflected in comfort of movement raises.

The hydrotransformer device

Hydrotransformer AT design

1  — the  Cranked shaft
2  —  Privodnoj a disk
3  — the  Frictional washer with a wavy spring
4  —  Dempfer of elastic fluctuations
5  —  Blocking муфта
6  — the  Casing pump wheels

7  — the  Pump wheel
8  — the  Turbine wheel
9  — the  Reactor
10  —  Mufta of a free wheeling
11  — the  Leading shaft

The hydrotransformer represents not folding design filled with oil consisting of a pump wheel, a turbine wheel, the reactor and blocking муфты.

The pump wheel through приводной a disk is directly connected with cranked shaft of the engine. The plug of a drive of the oil pump which carries out function of forcing of pressure in a hydraulic part of a control system and system of greasing АТ is welded on a pump wheel.

Transformation mode. Transformation is made in a certain range of twisting moments of the engine, thus the reactor, thanks to functioning муфты a free wheeling has rigid communication with картером transmissions.

Mode гидромуфты. In a mode гидромуфты twisting moment transformation is not made and to a shaft of a turbine wheel of the reactor the hydraulic way transfers a constant twisting moment developed by the engine. In this case the reactor any more has no rigid communication with картером and freely rotates together with a stream of a working liquid.

Blocking mode. In a blocking mode pump and turbine wheels are rigidly connected blocking муфтой. At certain turns of the engine the control system gives out a command on blocking of the transformer and all capacity developed by the engine is transferred to a target shaft of the hydrotransformer, passing a stage of hydraulic transformation. Thus proslipping in the transformer (a difference of turns of turbine and pump wheels) is completely eliminated that in turn leads to decrease in turns of the engine and, - as consequence, - to reduction of the expense of fuel and decrease in level of a noise background.

The oil pump

The oil pump has лопастную a design and is located between the hydrotransformer and a transmission. The pump has variable productivity and copes the pressure of a feedback submitted from a regulator of pressure.

Planetary transmission

Design of planetary assemblage

1  —  Drove a planetary number
2  —  Satellites
3  — the  Big central wheel (эпицикл)
4  — the  Small central wheel (sun)


In a transmission two planetary numbers (forward and back) with одновенцовыми the satellites, four blocking муфты (муфты reverse gear inclusions, муфта inclusions of the higher transfers, муфта a forward course and муфта maintenance of a mode of braking with the engine), one tape brake, one disk brake and two муфты a free wheeling (switchings of 1/2 and 3/4) are used. The box design provides realisation of four forward transfers and one back. The box possesses three degrees of freedom in view of what for reception of any transfer relation paired inclusion of elements of its management is required.

The main transfer and differential

In АТ the main transfer гипоидного type is used. A leading shaft-gear wheel of the main transfer it is placed in the dual conic roller bearing established in the case of the oil pump and the second roller bearing, located in the console картера transmissions. The conducted gear wheel is placed in картер differential.

Adjustment гипоидной transfers is made by selection of the lining demanded on a thickness established between an external holder of the dual conic bearing and the case of pump assemblage.

On the back end of a leading shaft-gear wheel the conducted gear wheel of intermediate transfer is established.

Differential gear wheels are fixed on power shafts by lock rings

The leading gear wheel of a drive of a speedometer is established directly in картере differential and connected to the flexible cable leaving the right wall of the hydrotransformer. Do not forget to grease a speedometer drive periodically.

The mechanism of a choice of working range АТ

Design of the mechanism of the selector of ranges АТ

1  —  Carter of transmission
2  —  selector AT Lever (in car salon)
3  — the  Spring
4  — the  Valve of a choice of a range
5  — the  Plate
6  — the  Lever
7  — the  Executive lever in картере АТ
8  — the  Gauge-switch of position АТ
9  —  Privodnoj a cable


Design of the lever of selector AT

1  — the  Cover
2  — the  Switch of modes of functioning of transmission
3  — the  Button
4  — the  Spring
5  — the  Handle
6  — a  lever Cover
7  —  Privodnoj a cable of the switch of modes АТ
8  — the  Plate
9  — the  Sealing lining
10  —  the Clamp

11  — a  cable Cover
12  — the  Nut (2)
13  — the  Core тросовой assemblages
14  — the  Nut (1)
15  —  Draught
16  — the  Lever
17  — the  Remote plug
18  — the  Remote plug
19  —  Kolodka
20  — the  Pin

The mechanism of a choice of a working range consists of the lever of the selector established in salon of the central floor console, to the right of the driver, drive a cable, system of draughts, the valve of a choice of a range and the mechanism of blocking of a target shaft of a transmission providing connection of the lever of the selector with the valve of a choice of a range.

Moving of the lever of the selector involves moving drive a cable, thus the pin located on the end of the lever puts in action the gauge-switch of position АТ which signal is transferred to the management block (TCM).

On a shaft of the mechanism of a choice of ranges the plate and the lever are located. The plate is equipped by seven flutes, each of which corresponds to one of seven positions of the lever of the selector (Р, R, N, D, 3, 2 and 1). By means of the given flutes lever fixing in the set position is carried out.

While translating the selector lever in position “Р” works the mechanism of blocking of a target shaft of a transmission that possibility spontaneous скатывания the car under a bias is prevented.

The mechanism of blocking of a target shaft of a transmission

At blocking of a target shaft of a transmission the latch end gets to a flute of a gear wheel of the blocking mechanism. The gear wheel is located on a shaft of a leading gear wheel of intermediate transfer.

While translating the selector lever in position “Р” draught of the blocking mechanism is displaced back. In a back part of draught the spring and a cam are established, and the cam can freely move concerning draught. Draught and a cam are included into gearing with a V-shaped flute connected with картером transmissions of the executive mechanism and a latch. In such position, in case of draught moving back, the cam moves to a back part of a latch and a V-shaped flute. The latch starts to turn in a direction of a gear wheel of the blocking mechanism and enters into gearing with its flute. If the latch end gets on a gear wheel tooth the cam ceases to move and as a result further moving of the lever the spring starts to be compressed. Under the influence of effort developed by a spring the cam gets to a flute of a gear wheel of the blocking mechanism. If the lever is translated in other position the cam under the influence of a returnable spring turns in an opposite direction, releasing a blocking gear wheel.

Control system of a drive of back wheels

The given system by means of electronic блокиратора operates муфтой a drive of back wheels. The system has been developed for the first time by experts of company Subaru and consists of the block of management of pressure in бустере муфты, the gauge of speed of movement of the car (VSS) and the electromagnetic valve.

In memory of the electronic block are stored optimum for various service conditions of a vehicle of value transferred муфтой a twisting moment. Being based on a combination of operational parametres of the car (speed of movement of the car, position throttle заслонки, positions of the lever of the selector, proslipping of wheels, etc.), the management block chooses from memory the corresponding factor of a drive of back wheels in the maximum degree answering to current conditions. The given factor serves as operating signal for formation by the electromagnetic valve of corresponding pressure in бустере муфты managements of a back drive.

Appointment of working ranges АТ

Position “Р”

Gets out at a car parking. In this position, in transmission all elements of management are switched off, and its target shaft is blocked, - car movement is impossible. To translate the selector in position “Р” follows only after a full stop of a vehicle.

Selector transfer in position “Р” during movement can lead to a transmission exit out of operation!

Position “R”

Backing. To translate the selector in a position “R” it is possible only after a full stop of a vehicle.

Inclusion of a reverse gear during car movement can lead to a transmission exit out of operation!

Position “N”

Neutral position. In a box all elements of management that provides absence of rigid kinematic communication between its conducting and conducted shaft are switched off. The mechanism of blocking of a target shaft is thus switched off, i.e. the car can freely move. It is not recommended to switch transmission in position “N” at movement накатом.

At all do not switch off ignition at movement under a bias!

Position “D”

The basic mode of movement. Provides automatic switching with the first on the fourth transfer. It is recommended at movement in normal conditions.

Position “3”

Movement on first three transfers is authorised. It is recommended to use at movement on hilly road or in the conditions of frequent stops (an intense city cycle).

Position “2”

Movement only on the first and second transfers is authorised. Rekomen-pouts to use, for example, on twisting mountain roads. Switching on the third and fourth transfers is forbidden. On this range the mode of braking is effectively used by the engine.

Position “1”

Movement only on the first transfer is authorised. This range allows to realise as much as possible a mode of braking by the engine. It is recommended at movement on abrupt descents, liftings and impassability.