Automatic transmission: replacement or repair?

A modern automatic transmission is a rather complex unit, which includes not only mechanical components, parts, but also has a lot of electronics. Therefore, automatic transmission repair often results in a decent amount. Naturally, in the event of a breakdown of the “machine”, the car owner has a question: to buy a new box, contracted, or contact a specialized technical center? Everywhere there are nuances, which should be dealt with in more detail.

Buying an automatic transmission

There are two options: buying a new unit or a contract one. A box from a dealership is expensive (RUB 700-800 thousand for a car in the middle and premium price category, not counting the work on replacement), it makes sense to buy it if the car has low mileage and is “modest” in age. Otherwise, when car "wound up" 100 thousand km or more, and was produced about ten years ago, purchasing a new "automatic" is unlikely to be advisable.

Buying a contract automatic transmission is almost always associated with risk. Relative exceptions include the option when they sell the box to you, put it in the same car service and give a (albeit short) guarantee. Usually in such workshops they change your faulty "machine" to a "used" working one. In other cases, you get a "pig in a poke", however, for a relatively small price. For example, for a used JF 414E automatic transmission for Lada Granta, they ask for an average of 30 thousand rubles. (a new one will cost 145 thousand rubles).





There is another option - to sell a car with a faulty box. However, first it is advisable to figure out what happened to the unit. It is likely that the box can be repaired and often for not very much money. That is, first carry out diagnostics, which will cost 1-5 thousand rubles.

Repair

If after checking the box you decide to restore it, first of all look for a good workshop. It is desirable that it be specialized and repair automatic transmissions of one brand or manufacturer. The main stages of accepting a box for repair in a good car service:

• ? if the “machine” is partially working, it will be checked “on the go”
  
• ? the master will definitely ask under what conditions you found a defect
  
• ? oil will be checked, which could cause a breakdown
  
• ? using computer diagnostics
  

During the repair, the specialist identifies faulty parts, replaces them. Then the box is assembled and installed back. Next, the “firmware” of the electronic unit is carried out (there may be two of them). At the last stage, the automatic transmission is checked on the trip. If the workshop values ​​its customers, a guarantee is given for 1-3 months.

Repair nuances: electronics in an automatic box

Often, the car owner panics when the first signs of a unit malfunction appear. However, you should not immediately look for big money to repair the "machine". Most often, the cause of the breakdown is electronics, the restoration of which is relatively inexpensive. But how to determine that it is the automatic transmission computer or other electronic components that are to blame?

Some speeds won't turn on

In this situation, the box goes into emergency mode, as evidenced by the indicator on the dashboard. The trip may be accompanied by shocks, light bumps during automatic gear shifting. Solenoids (coils with wire wound around them) are usually the culprit. Their verification is carried out using computer diagnostics or elementary resistance testing. Only partial disassembly of the box is required. The repair consists in replacing the blocks of solenoids, which will cost 10-30 thousand rubles.

Automatic transmission goes into "emergency gang" when the selector is moved to position "D"

This situation indicates a malfunction of the sensor that controls the rotation of the input and output shafts. Computer diagnostics are also needed to identify the breakdown. The cost of the sensor and services for its replacement are unlikely to exceed 5 thousand rubles.

The selector position icons displayed on the instrument panel do not correspond to reality

Also, there may be no indication at all. It's all about the selector position sensor. Sometimes not even in it: if water got on the part, the contacts could oxidize. The sensor itself costs less than 5 thousand rubles, and the replacement is made in no more than 1 standard hour.

The automatic transmission is constantly in emergency mode

Sometimes it turns on after warming up the oil in the box. There is a problem with the temperature sensor. You can identify a breakdown by computer diagnostics, it is easier and better to check the performance of a part by installing a known-good spare part (some services provide such a service). The price of the sensor, depending on the automatic transmission model, is from 500 to 5 thousand rubles.

Why do machines fail?

The most banal reason is an untimely oil change, its lack or the use of the wrong composition recommended by the manufacturer. The second reason is the incorrect operation of the box, which consists in driving with sharp accelerations, braking (“sporty style”) and insufficient warming up in winter. In the latter case, there is a common misconception when the driver, using the preheater, thinks that the oil is also thinning in the automatic transmission. To bring the box into working condition in frost from -5 to -15 ° C:

• ? start the car
  
• ? wait until the engine temperature reaches 40-50 °C
  
• ? press the brake and put the selector in position D
  
• ? wait 5-10 minutes
  

During this time, the parts of the box will warm up and you can safely ride. If the frost is -25 ° C, keep your foot on the brake for 10-20 minutes. But even if you service the automatic transmission correctly and on time, use the right oil, the life of the unit will be reduced in any case if:

• ? the car is constantly driven with a trailer
  
• ? the car often slips in mud, snow
  

There are other ways to “bring closer” the repair. For example, the resource of the box will be reduced if you sharply change the position of the selector from D to R and vice versa. Some “thrifty” drivers, after a strong acceleration or downhill, move the lever to the N position, thinking that fuel consumption is reduced. But it's not "mechanics"! In reality, oil starvation of planetary parts begins, since the engine is idling and the pump cannot lubricate the automatic transmission elements in full.

How long does an automatic transmission "run"?

With proper operation and timely maintenance, the unit, together with the car, is able to cover 200 thousand, and in some cases all 300 thousand km. But again, there are nuances: it's no secret to anyone that some, including eminent manufacturers, installed unsuccessful automatic transmissions on their cars, which failed after 50-60 thousand kilometers. This is especially true of "raw" boxes - we mean new developments that are first installed on cars.

For example, PSA - AL4 (DP0), which is a joint "brainchild" of three companies at once - Renault, Peugeot and Citroen. The solenoids constantly overheated in the box. In 2010, the problematic unit was replaced with an AT8. Or 6T30 and 6T40 from General Motors, which were equipped with Chevrolet cars: Aveo, Cruze models, released before 2012. Aisin makes great boxes, but it has its own skeletons in the closet. These are the U140, U260 and U660 units installed on Toyota. Problems with valve body failure due to overheating are found on RAV4, Camry models produced in 2004 and 2005.

Conclusions

It is impossible to recommend anything specifically and immediately here. A lot depends on the correct diagnosis, and therefore, on the workshop, which should have all the necessary equipment, and most importantly, intelligent specialists. So the best option is to first contact the service, and not guess what is better - a contract box or a repair comparable to it in price.