Toyota Land Cruiser 100/Amazon, Lexus LX 470

since 1997 of release

Repair and car operation

Automatic transmission (AT)

General information

For a complete set of models considered in the real Management one of two types of 4-step automatic transmissions (with raising transfer) can be used: А343F and А440F, and since 2002 вып. – 5-step AT. All transmissions are equipped with the being blocked converter of rotation (hydrotransformer). The converter provides direct coupling between the engine and driving wheels of the car.

In view of complexity of a design of AT, absence on free sale of replaceable internal components, and also need of use of the special equipment, originators of the real Management do not recommend to owners of cars to carry out major maintenance of transmission by own forces. In the present Chapter procedures of diagnostics of the general refusals of AT, its routine maintenance, the main adjustments, removals and installations are considered only.

Sometimes, in case of serious breakage, it is more reasonable and simpler to replace transmission, than to waste time and funds for restoration of the failed assembly. Regardless of the chosen way of introduction of refused AT in action, independent performance of its removal and installation will help to cut down substantially expenses (before make sure that transmission really needs regenerative repair).

Functioning principle

Assembly of typical AT

Automatic transmission consists of the hydrotransformer with the blocking coupling, a raising planetary row, a transmission, a transfer case and a control system which structure includes hydraulic and electronic parts (address to an illustration above).

Planetary assembly of transfers consists of two planetary ranks. The structure of a transfer case includes a planetary row with frictional elements of management (the blocking coupling and a brake). Work of all transmission the electronic control unit operates. Switching of high-speed modes is made by means of the car established in salon selector growling. The selector is connected by means of a cable to klapanny assembly, and with its help it is possible to set a range of used transfers. Besides the selector in salon for a task of special modes of functioning of transmission some switches are provided.

For prevention of breakages of AT at the wrong choice of a high-speed range, for example, moving from «D» in «R» on the lever of the selector the clamp is provided, – "dangerous" switchings can be carried out only at the pressed button of a clamp. The lever of the selector can be established in one of six fixed provisions: "R", «R», «D», «N», «2» and «L», purpose of each of which is considered below.

Situation "R"

Gets out at a car parking. In this situation, in transmission all elements of management are switched off, and its target shaft is blocked, – movement of the car is impossible. To transfer the selector to the situation "R" follows only after a full stop of a vehicle.

Situation "R"

Backing. To transfer the selector to a position of "R" it is possible only after a full stop of a vehicle.

Situation "N"

Neutral situation. In a box all elements of management that provides absence of rigid kinematic communication between her leader and conducted in bulk 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 the situation "N" at movement nakaty.

Situation "D"

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

Situation "2"

Movement only on the first and second transfers is authorized. It is recommended to use, for example, at movement 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.

Situation "L"

Movement only on the first transfer is authorized. This range allows to realize as much as possible a mode of braking by the engine. It is recommended at movement on abrupt descents, liftings and off road terrain.

OD mode

Permission to use of the fourth, raising, transfers is carried out by means of the special OD button. If the button is in the drowned condition and the lever is established in situation "D", switching on raising transfer is authorized. Otherwise inclusion of the fourth (raising) transfer is forbidden. The control system condition in this case is determined by a control lamp of "O/D OFF". In case of permission of raising transfer the indicator does not burn, at a ban, burns. The mode is used at movement with constant speed on direct sites of the highway. It is necessary to avoid O/D mode use in city conditions, especially in a winter season when braking by the engine gains the vital value. It is not necessary to include also a mode of raising transfer at a full load of the car.

Special programs

On cars from AT two control modes by gear shifting are put: "economic" (NORMAL) and "sports" (POWER). The choice is carried out by means of the special switch which has been built in in the central console of the car.

Economic mode (NORMAL)

In this mode the minimum consumption of fuel takes place. Gear shiftings occur in the middle of the corresponding ranges of the engine, nature of movement of the car quiet, smooth.

Sports mode (POWER)

At inclusion of this mode on the panel of prior the control lamp of "ECT POWER" lights up. In this mode there is the maximum selection of engine capacity, switching of a box is made in the top border of the corresponding ranges of turns of the engine. Acceleration performance of the car substantially increases, fuel consumption, respectively, increases.

Planetary transmission

The structure of a planetary transmission includes three planetary rows, three blocking couplings, four brakes and three couplings of a free wheeling.

The capacity from the engine via the hydrotransformer is transferred to an entrance shaft of a planetary transmission.

Gear shifting is carried out by inclusion of a certain combination of brakes and couplings of a free wheeling therefore frequency of rotation of a target shaft changes.

The transfer case contains one more planetary row, two blocking couplings and one brake.

Device of a hydraulic part of a control system

Transmission

The hydraulic part of a control system consists of the oil pump, klapanny assembly, electromagnetic valves, couplings and brakes, and also the channels connecting among themselves listed elements. Pressure of working liquid created by the pump is used for management of frictional elements of transmission, hydrotransformer and greasing feed. In klapanny assembly three electromagnetic valves of switching are established. With their help the electronic block exercises administration of gear shifting and hydrotransformer blocking.

Transfer case

Into structure of a hydraulic part of a control system of a transfer case enter: a klapanny box, the electromagnetic valve No. 4, a brake (В4), two blocking couplings (SZ, С4), and also the channels connecting among themselves listed elements (address to an accompanying illustration). Purpose of a box – management of a planetary row which can be carried out or manually, or automatically electronic block.

Assembly of a transfer case is presented on an illustration below.

Assembly of a transfer case

Electric part of a control system

The electric part operates gear shifting in a transmission and a transfer case, and also the blocking coupling of the hydrotransformer. It consists of three parts: sensors of speed of movement of the car (VSS), the sensor of provision of a butterfly valve (TPS) and the other information sensors tracing parameters of a condition of transmission and transferring data of ECM (the electronic control unit); ECM which on the basis of the analysis of data arriving to it defines the switching moments in a transmission and a transfer case, and also operates the blocking coupling of the hydrotransformer; and the executive part consisting of four electromagnetic valves.