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Signs of malfunction of the torque converter automatic transmission BMW, Subaru, Mazda Premacy

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Signs of malfunction of the torque converter automatic transmission BMW, Subaru, Mazda Premacy
Signs of malfunction of the torque converter automatic transmission BMW, Subaru, Mazda Premacy

The torque converter is one of the main elements in the automatic transmission system. Due to it, smooth and timely gear changes in the vehicle are carried out. The first torque converter systems were developed at the beginning of the last century, and today they have been significantly modernized. But, despite all the improvements and technological progress, sometimes the box fails. Let's look at the main signs of an automatic transmission torque converter failure in the most popular car models and brands.

signs of a malfunctioning automatic transmission torque converter

The principle of the torque converter

Technologies are constantly evolving, and the design of automatic transmissions is becoming more complicated along with them. Today the torque converter inautomatic transmissions also takes over the functions of the clutch. At the moment one of the gears is engaged, this system breaks the connection between the engine and transmission. After turning on the lowering or increasing speeds, the element takes away part of the torque. This is necessary to ensure the smoothest possible shifts.

automatic transmission torque converter signs of malfunction


A typical torque converter is three rings with blades. All these parts rotate, while they are located in a single housing. Inside the latter is the transmission fluid. It lubricates and cools the moving parts in the transmission system. The torque converter is mounted on the crankshaft and then connected directly to the automatic transmission mechanism. The liquid moves inside the body with the help of a special pump - a pump. This part allows you to create the oil pressure necessary for the operation of the unit.

Features of modern gas turbine engines

Modern automatic transmission systems are equipped with torque converters that are fully electronically controlled. A huge number of sensors monitor various parameters of the device. With all the manufacturability, the complexity of the design is not the best way reflected in the reliability. Today, even on expensive and luxury cars, manufacturers can install frankly bad boxes.

According to theory, the torque converter has a long service life. It is comparable to the resource of the entire automatic transmission. But sometimes, like any other mechanism, it can fail. The unit should be repaired, but inIn some cases, only a replacement will help. It is necessary to know the signs of a malfunction of the automatic transmission torque converter in order to notice the problem in time and begin repairs. We'll take a look at them below.

automatic transmission torque converter signs of malfunction subaru

Main symptoms of torque converter failures

Owners of cars equipped with automatic transmission should know the main symptoms of a breakdown. If soft mechanical sounds are heard during the shifting process, and when revving and under load they disappear, then this indicates problems in the support bearings. The problem can be solved by opening the assembly and inspecting them. These parts may need to be replaced.

Also, signs of a malfunction of the automatic transmission torque converter are vibrations. Especially often they are observed when driving at speeds in the range of 60-90 km / h. As the situation worsens, the vibrations will only increase. This often indicates that the working fluid has lost its properties, and its wear products have deposited in the oil filter and clogged it. The problem can be solved by changing the filter and oil in the engine and automatic transmission.

If there are certain problems with the dynamics of the car, then this is not necessarily an automatic transmission torque converter. Signs of a malfunction (the photo of this one was located in the article) in this case is the lack of dynamics, and the reason is related to the failure of the overrunning clutch. If the car has stopped and is not going anywhere else, then this should also be regarded as one of the symptoms of problems in the automatic transmission. Often this behavior can indicate damage to the splines.on the turbine wheel. Repair involves the installation of new splines or a complete replacement of the entire turbine element.

If rustling sounds are clearly audible when the engine is running, then these are also signs of a malfunction of the automatic transmission torque converter. The problem lies in the bearing, which is located between the turbine wheel and the cover. In the process of movement, such a sound may periodically appear or disappear. This is a signal to contact the service as soon as possible. A visit here should not be postponed. If loud sounds are heard when shifting gears, then the blades are deformed and fall out. The repair is simple and not too expensive. Specialists will replace the failed turbine wheel.

automatic transmission torque converter signs of malfunction photo


The owners of these cars rarely encounter breakdowns caused by the automatic transmission torque converter. The symptoms of a Subaru malfunction are practically no different from the symptoms of automatic transmissions from other manufacturers. The most common signs are vibrations and various extraneous noises during the operation of the box. Also, in case of problems, jerks are felt at the moment of switching at speeds of 60-70 km / h. Lost dynamics. It becomes very difficult to accelerate the car. And another sign that is not related to the torque converter is a fluid leak.

automatic transmission torque converter signs of malfunction twitches

What most often fails on Subaru?

The most common failure for these vehicles is the lock piston friction lining. She wears out and outbuilding. In this situation, it is difficult to determine the breakdown. But if the transmission is not diagnosed in time, it will simply stand up. And then only replacement will help.

In new generation boxes (on six-speed automatic transmissions), where the oil in operating mode can reach 130 degrees, and the impeller can work in slip mode, there is another typical malfunction. This is too fast friction lining wear. Its products pollute the oil, clog the filter and valve body. As a result, the automatic transmission torque converter fails. The symptoms here are the same as in transmissions from other manufacturers.


Cars of this manufacturer have always been reliable. But as with other models, there are some nuances here. Some automatic transmissions were simply unsuccessful and "stillborn". Also, many scold individual models of units from ZF. Among the main causes of breakdowns is the automatic transmission torque converter. Signs of a malfunction - the box twitches, there are shocks when switching to "D", regassing at the time of switching, slipping and vibration.

Serious signs of damage include noise, jerks and “thoughtfulness” of the box. Perhaps the problem is not in the torque converter. But his diagnosis will not be superfluous. Signs of a malfunctioning BMW automatic transmission torque converter may not be noticeable to the eye at all, but this does not mean that they are not there. Often, transmission problems are associated with various errors in the electronics. ECU diagnostics will help here.


The popular 4F27E automatic transmission was installed on the Mazda Premacy. No one has any particular problems with her. Her mainadvantage is excellent maintainability. Experts say that it can be repaired even without the need for dismantling. Among the frequent malfunctions, the friction clutches burn out in the Overdrive and Reverse modes. Overrunning clutch burns out.

The design features of the automatic transmission are to blame. There are no special problems with the torque converter. In this box, the valve body often wears out, the solenoids fail. Few of the owners had signs of a malfunction of the automatic transmission torque converter. Mazda Premacy was equipped with a reliable transmission.

signs of malfunction of the torque converter automatic transmission mazda premacy

Faults in automatic transmission AL-4

This is a product of French engineers. This box was developed by specialists of the Citroen concern. It was the main automatic transmission for all French-made cars from 1998 to 2005. The unit turned out to be as simple and maintainable as possible. Although the box is not very smooth, it has good reliability. Owners rarely observe signs of a malfunction of the torque converter of automatic transmission AL4.

There are no special symptoms here - they are standard for all torque converter transmissions. The most important thing that many are afraid of in this box is the solenoids. They break down relatively often. There are also problems with the electronics. Because of this, the box often falls into error and goes into emergency operation.

If the car has been used for a long time in difficult conditions, there are also problems associated with the torque converter. The clutch is rotated, which is responsible forfree running of the reactor. This manifests itself as follows - the car does not move at low speeds in Drive mode, but starts off only when you press the gas.

signs of a malfunctioning torque converter automatic transmission bmw


It must be said that there are no specific signs indicating a breakdown of the torque converter. Sometimes even experts cannot determine what exactly is out of order. All this leads to diagnostic costs. The repair of the gas turbine engine itself is simple. The only difficulty is to dismantle the assembly. The repair process includes replacement of worn consumables, assembly and balancing.

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