What if the automatic transmission box jerks when the transmission is turned on? Diagnostics, operation and repair of automatic transmission

With the development of the automobile industry, in addition to the functional and external components, the units and aggregates of automobiles are improved and changed. The introduction of an automatic gearbox made it possible to ensure comfortable driving of the car, without the need to constantly squeeze the clutch and manually switch gears, as on a manual gearbox. Having become widespread in America, the automatic box has become popular all over the world. Currently, almost every car is delivered to the market with a complete set, in which there is an automatic transmission. It is installed on cars with rear and front-wheel drive.

Varieties

There are three main types of automatic boxes:

1) Classic hydraulic transmission. In it, the gear ratio is changed by locking the clutches of the planetary clutches using oil pressure.

2) Robotic automatic transmission. Switching is carried out by the electronic box control box. Allocate:

• Tiptronic - with the possibility of manual gearshift.
• DSG - a complex design and a well-designed scheme of operation, allows for a gear shift, which the driver does not feel. Also possible is the "Sport mode" with a rapid increase in torque.

3) Variator - change the torque by correcting the diameter of the master and the driven pulleys. Each type of automatic transmission is unique and requires a certain handling, maintenance and repair.

Checking the automatic transmission for serviceability

Every driver should know how to check the automatic box for correct operation. Correct automatic transmission operates smoothly and without extraneous sounds. The gear shift must not be accompanied by jerks, and the acceleration of the car should not be too late. This is evidenced by the correct and precise operation of all the components of the gearbox. The main role is played by the condition and properties of the oil, because it allows switching. The level of lubrication should be maintained. The liquid itself should be suitable for all parameters to the specific gearbox. Also, the color change and the presence of a large number of wear products are not allowed.

Malfunction of automatic transmission

Problems with automatic transmission, arising from its malfunctioning, are conventionally divided into faults related to the electronic, mechanical and hydraulic parts. The incorrect work of this or that part is accompanied by a number of features that are different and differently eliminated. Faults in the electronic part include the failure of sensors located in the box or the loss of contact between the sensor and the electronic control unit. As a result, the machine does not work correctly, and the "check" lights up on the instrument panel. Malfunctions of the mechanical part, such as wear of gears, shafts and friction elements, are accompanied by jerks when switching gears or by switching on a speed that is inadmissible in this mode of operation. In case of hydraulic failure, the nodes and mechanisms of hydromechanical transmission fail. Causes - clogging of oil channels or breakage of the oil pump. The most common fault occurs when the automatic transmission jerks when the transmission is turned on. This will be discussed below.

Causes of jerks during the switching of speeds

The reasons for which the automatic transmission box jerks when the transmission is switched on are directly related to the above mentioned faults. Durability of the automatic transmission depends on the manner of riding the driver and oil, which is poured into the box. Quick start from the place, rapid acceleration of the car and sudden switching of gears are unacceptable, otherwise the required oil pressure will not be created. Mechanical and friction elements simply do not have time to work in time, which increases their wear and tear. As a result, the automatic box jerks when switching.

Now a few words about lubricants. Oil in the automatic box should be poured with special care. Here is filled transmission with the ATF marking, which in its properties should match this box. A low level creates insufficient pressure, and the automatic box jerks when the gear is turned on. The oil itself can not be mixed with a liquid of another brand. It must be red and can not contain a large number of wear products. This leads to clogging of the channels (pressure reduction) and increased wear of rubbing parts (gears, shafts and friction elements). Another possible cause is a poor warming up of oil in the crankcase or a malfunction with the engine itself. The motor with the box is tightly connected, and the constant torque changes are reflected in the movement.

Repair box

For the repair of automatic transmission the price will always be considerable due to the high cost of parts, the availability of special equipment and the complexity of the work itself. Quite often the price tag reaches 1 thousand dollars. Independently to eliminate a malfunction when the automatic box twitches at inclusion of transfer, not possessing the certain knowledge and the tool, it is practically impossible.
In the presence of experience and free time, the box needs to be removed from the engine, having drained the oil from it. This is also not an easy process, especially on the front-wheel drive car.

What next?

Then the torque converter is withdrawn, the back cover of the crankcase is unscrewed, which is removed by hammer blows on special protrusions. Then, on the reverse side, the oil pump is unscrewed, and the gears with shafts and planetary gear are removed from the front. From the pallet of the box, the hydraulic control unit is dismantled. All removed elements are disassembled and inspected for damage and wear. Damaged or severely worn parts are replaced by similar ones, their work is checked, and then the whole construction is assembled in reverse order. Such repairs are a fairly responsible and time-consuming process. Therefore, in the absence of experience, you should contact the service station. Currently, for the repair of automatic transmission the price varies from 5 to 25 thousand rubles.

Maintenance and operation

For normal and durable operation of automatic transmission it is necessary to adhere to the following rules for maintenance and operation:

• The first is to carry out the maintenance in time: constantly monitor the oil level, change it with a filter every 60 thousand km. If the car is operated in difficult conditions, then the oil should be replaced every 40 thousand km.
• Before starting the car, it is necessary to squeeze out the brake pedal, turn on the gear and wait a while (1-2 seconds) to get the right oil pressure in the box and the clutches to work. Then, gradually releasing the brake pedal, start moving. While driving it is undesirable to press the accelerator pedal sharply to avoid increased wear of rubbing elements.

Conclusion

Summing up, we can say that the automatic box provides comfort and is very convenient to use. And if you adhere to all the above-mentioned rules of operation, carry out maintenance in time, and oil in the automatic box, fill only the high quality, then the life of this gearbox will be large, and it will not give the driver unnecessary difficulties.