The design of the automatic transmission includes a torque converter, oil pump, planetary gears, friction clutches and brakes. All mechanisms are controlled by an electronic unit. At the same time, it monitors the state of all its electrical components. If a malfunction occurs, the maintenance indicator light will light on the instrument panel. The codes of detected faults are stored in the memory of the electronic control unit. To read fault codes, an external diagnostic device, a scanner, must be connected to the diagnostic connector.
The torque converter is mounted on the engine flywheel. During operation, it is filled with working fluid and, rotating at a sufficient speed, transmits torque from the engine to the input shaft of the gearbox, absorbs and smooths out vibrations and jerks from the operation of the engine and gearbox. The torque converter consists of three wheels: pump, reactor and turbine, and also includes its locking clutch. The pump wheel is integrated with the torque converter housing and is secured to the engine flywheel. The turbine wheel is connected to the input shaft of the gearbox by a splined connection. When a certain speed is reached, the torque converter is locked using a clutch, thereby ensuring a rigid connection between the engine crankshaft and the transmission. This significantly reduces power losses and has a positive effect on dynamic performance and fuel consumption.
Planetary gears are installed directly in the automatic transmission housing and are designed to change the gear ratio and engage reverse gear. The planetary mechanism (transmission) consists of four main elements: the sun gear, the planet carrier with satellites and the crown gear. The gear ratio and direction of rotation are changed by locking or unlocking two of the three elements (sun gear, carrier, ring gear) in various combinations.
Friction clutches and brakes are designed to lock various elements of planetary mechanisms. They are activated by the pressure of the working fluid when the corresponding valve opens. The valves are opened in a certain sequence by the electronic control unit depending on the speed and position of the gas pedal, the crankshaft rotation frequency, etc.
The automatic transmission uses a special working fluid; during the operation of the vehicle, it must be replaced in accordance with the maintenance plan. Also, when performing each maintenance, you should make sure that there is no leakage of working fluid from the gearbox. If oily leaks are detected on the crankcase, it is necessary to check the level of the automatic transmission fluid and, if necessary, eliminate the malfunction as soon as possible.
The gearbox is a technically complex unit, which should only be serviced and repaired at a specialized service station.
Automatic transmission
| Gearbox type | hydromechanical |
| Number of gears | 6 |
| Working fluid recommended by the manufacturer | DEXRON VI |
| Volume of liquid, l | 8.0 |
Warning!
An automatic transmission is a reliable vehicle component with a long service life, but subject to regular maintenance and careful operation. The reasons for the reduction of its service life and failure may be:
- untimely replacement of working fluid;
- the ingress of sand or other foreign particles into the internal cavities of the automatic transmission;
- operation with abnormal working fluid level (both low and high);
- use of a non-recommended type of working fluid.
Towing a vehicle on a flexible or rigid hitch is permitted only in forward motion, for a distance of no more than 100 km and at a speed of no more than 80 km/h. In this case, the automatic transmission selector mode lever must be in position N (neutral). Towing a vehicle over a long distance is only permitted with the drive wheels suspended.
To avoid damage to the automatic transmission, do not move the selector lever to position P while the vehicle is moving.