Four-speed automatics have long been established in the car market and continue to be popular. Motorists love them for comfort, ease of gear shifting, reliability and a very low price. But progress does not stand still, and manufacturers equip new car models with six- and even eight-speed automatics. The six-speed automatic is no longer a novelty - it has been on the market for several years. But many car owners and people who are just about to purchase their first vehicle are tormented by doubts about how many steps are enough, and whether it is worth overpaying for a “six-step”.
Advantages of the 4-stage version
Many drivers praise the common four-speed gearboxes and distrust the newfangled six-speed automatic transmission. They give the following arguments:
- Unreliability. Four gears are better because they've been around for a long time and are more reliable, and automatic transmissions with more gears will break down more often.
- Money spendings. Firstly, the “six-speed” itself is more expensive than a four-speed box. Secondly, its repair will also require additional costs, since the automatic transmission mechanism is more complicated there, and in combination with the first point, a six-speed gearbox generally becomes a huge hole in the budget of a car owner with such a transmission.
- No difference. Also, supporters of the four-speed automatic claim that there are no differences in driving sensations with different automatic transmissions, and they do not see the difference at all. Moreover, in their opinion, there are no differences in the technical part: fuel consumption, speed, smooth switching.
However, one should not draw hasty conclusions, since all these arguments are erroneous. A six-speed automatic is far from a new item in the automotive industry, and all the errors (which may have been found in the first generations of cars with such boxes) have long been fixed. The designs of these boxes are very similar, which means that it is impossible to judge which of the automatic transmissions is more reliable and practical - most likely, they are the same in this parameter.
A six-speed automatic is really more expensive, and its repair in a service center will also require considerable costs. But repairing an automatic four-speed gearbox is also not cheap, and it breaks down no less often, that is, you overpay only initially, for the box itself.
Arguments in favor of 6-speed type
Now let's talk about the differences, but they really are, and there are a lot of them. All these points can be considered the advantages of a six-speed automatic transmission compared to a four-speed one.
- Comfort while driving. Due to the presence of more automatic transmission gears, they will shift more often and more smoothly, which means that during the trip there will be no sharp shocks with each gear change. In order to properly shift gear using a four-speed gearbox, you need to re-gas, since there are not enough steps in this case. With a large number of steps, this problem does not arise, so it shifts more smoothly.
- Fuel consumption. A larger number of gears allows you to select the optimal stage for a given speed more accurately so that the number of engine revolutions is minimal. This allows you to significantly save gasoline consumption in cars with a six-speed automatic transmission.
- Speed. The number of gears has little effect on the maximum speed of the car, other parameters are important here, such as engine power or exhaust system. However, a larger number of steps will ensure smooth acceleration, thereby reducing its duration. At higher speeds, it's hard to feel the difference. Let's just say that the optimal transmission reduces engine speed, reduces not only fuel consumption, but also the wear of some car systems.
Summarize
Thus, the question of the advisability of buying a car with a six-speed automatic box is no longer relevant. Driving such a car will be more comfortable and smooth. You can also reduce fuel consumption and save a lot of money. This is where a situation arises where more passes are indeed better. An eight-speed also has more gears and will be more comfortable than a six-speed.
Cars are constantly evolving and improving, and progress should be treated with great interest, because it is curious to try more advanced technologies than to constantly use old, and not always more reliable mechanisms. Therefore, if you have a couple of extra tens of thousands of rubles, feel free to buy a car with six gears on an automatic transmission, and you definitely will not regret buying it.
A car with automatic transmission is increasingly becoming the choice of residents of the metropolis. If earlier this option could only be found on cars of the middle and higher price segments, and on used "foreign cars" brought from the States, today cars of absolutely all classes are two-pedal.
"Comfortable!" - the most frequent argument of car owners tired of "traffic jams". And, indeed, the automatic transmission greatly simplifies the process of movement in a bustling metropolis, reducing the number of driver actions to a minimum. The choice for most representatives of the beautiful half of humanity is not worth it at all - the box is only an “automatic”. Even after “passing” the exam at a driving school, not all novice motorists understand what the leftmost pedal is responsible for, and what the location of five or six numbers on the “joystick” that sticks out of the floor means. But what lies behind the familiar word "automatic"? After all, there are not one or two varieties of a box without a clutch pedal today. And some, especially cunning car sellers, pass it off as an automatic - a robotic gearbox, which has much more in common with the usual "mechanics".
How to choose an automatic transmission, we will try to figure it out.
Torque converter gearbox
The most common car gearbox in the world. It was from her that the abbreviated name of the box went - “automatic”.
The torque converter itself is not part of the gearbox and, in fact, performs the role of a clutch, transmitting torque when starting the car. At speed, at high speeds, the torque converter is locked by the clutch, reducing energy (fuel) consumption. In addition, the torque converter is a good damper for various vibrations, both of the engine and the gearbox, thereby increasing the resource of both units.
There is no rigid connection between the engine and the mechanical part of the automatic transmission. Torque is transmitted through gear oil, which circulates under pressure in a closed circuit. It is this scheme that ensures the operation of the engine with the gear engaged when the car is stationary, and that is why so much attention is paid to the quality of transmission oil.
The hydraulic system, and in particular the so-called valve body, is responsible for shifting gears. In modern "automatic machines" it is controlled by electronics, which allows the transmission to operate in different modes: standard, sporty or economical.
Despite the apparent complexity, the mechanical part of the torque converter automatic transmission is quite reliable and maintainable. Its most vulnerable point, as a rule, is the valve body, the malfunctioning of the valves of which is accompanied by unpleasant shocks during switching. In most cases, it is “cured” by replacing an expensive part.
As noted above, you need to monitor the condition of the oil. Although today there are already so-called maintenance-free automatic gearboxes that do not require an oil change at all.
The driving characteristics of modern cars equipped with a classic "automatic" are very much dependent on the control electronics, which receives information from numerous sensors. Reading information from them, the “brains” of the car’s automatic transmission send a command to shift gears at the right moments. This behavior is also called “box” adaptability. So regular software updates of the "machine" can significantly improve the characteristics of the car's behavior.
An important factor is the number of transmission gears. Now there are still hydromechanical transmissions with four steps, but most automakers have switched to “automatic boxes” with five, six, and even seven and eight gears. The increase in the number of gears has a positive effect on smooth shifting, dynamics and fuel economy.
The manual shift mode, which first appeared on Porsche cars under the name Tiptronic and was instantly copied by almost all manufacturers, is, in fact, just a fashionable “chip”. If in sports cars driven by experienced drivers, switching to manual mode can significantly affect the behavior of the car, then in the mundane life of mass cars it is, in general, useless, and they buy an “automatic” not in order to shift gears with their hands.
Considering the combination of all factors, we can say that the automatic torque converter transmission of the car most effectively manages the distribution of engine torque, is easy to maintain and is the most justified choice.
Examples of vehicles with a torque converter gearbox:
Continuously Variable Automatic Transmission (or CVT)
CVT or Continuously Variable Transmission - this is how the variator is most often indicated. Although externally this transmission is no different from the usual “automatic box”, it works on a completely different principle.
There are no gears at all in the variator, and nothing changes in it. The change in gear ratios occurs continuously and constantly, regardless of whether the car is slowing down or accelerating. This explains the absolute smoothness of the operation of the continuously variable transmission, which provides comfort in the car, protecting the driver from any shocks and shocks.
True, manufacturers are virtually introducing five or six gears into the variator that can be "switched". But this is nothing more than an imitation that allows the variator to work in the modes necessary for the driver.
If we omit the technical details as much as possible, the design of the variator consists of two pairs of cone-shaped pulleys, between which a belt rotates along a variable radius. The sidewalls of the pulleys can move and move apart, thereby providing a change in gear ratios. The belt itself, on which the main load falls, is a complex engineering device and looks more like either a chain or a tape assembled from metal plates.
In addition to smoothness, the advantage of the variator is the speed of its operation. Since the CVT does not waste time shifting gears, for example, during acceleration, the continuously variable “box” immediately finds itself at the peak of torque, ensuring maximum acceleration of the car. True, subjectively, this feeling is hidden by the same lack of switching.
Of the features of operation, it is worth noting the higher cost of maintaining the variator compared to the classic “automatic” gearbox. This is explained by the fact that the stepless "box" is afraid of overheating. High temperatures inside the "box" require the use of a special and very expensive oil, which must be changed, on average, every 50-60 thousand kilometers. And after 100,000 km, the belt will most likely require replacement.
Examples of cars with a CVT:
Audi A4 2.0 Multitronic
Robotic gearbox
A more correct name would be - a manual transmission with automatic clutch, since only the number of pedals makes it related to the "automatic". "Robot" completely repeats the scheme of operation of a conventional manual gearbox, with the only difference - two servos are engaged in clutch release and gear shifting, under the control of an electronic unit. Moreover, the automatic gear shifting mode is secondary.
The robotic transmission has in common with the “mechanics” that gear shifting occurs with a break in the flow of torque, which is expressed in pauses-dips during acceleration.
On a conventional manual transmission, this failure also exists, but at this moment the person behind the wheel is just busy with the process of depressing the clutch and turning off / on the desired gear. And when the automation does everything for the driver, attention is focused on the “pause” and a feeling of this failure is created.
However, this effect can be combated. First of all, you need to forget about the automatic mode, like a bad dream, and shift gears yourself with the obligatory (!) Regassing: unpleasant dips will be reduced to a minimum, or even disappear altogether.
In addition, the "robot" requires a mandatory shutdown in neutral at each stop for more than a few seconds, saving the clutch from overheating. The “robot” will not allow to slip for a long time, leaving, for example, from a snowdrift, notifying the owner with the smell of a burnt clutch and going into emergency mode.
Why is such a transmission needed at all? Of course, there are advantages too. Firstly, this is, of course, a moderate price of a “robot”, compared to full-fledged automatic transmissions: the cost of such a transmission as an option usually does not exceed 25,000 rubles. Secondly, moderate fuel consumption, which remains at the level of a car with a conventional manual transmission.
Also, some manufacturers equip “robotized” cars with paddle shifters that allow you to change gears very quickly, winning in dynamics even from the same car equipped with a manual “box”.
But, in general, the disadvantages of such a transmission as an “automatic” overlap the advantages. Although some manufacturers stubbornly continue to equip some of their models with robotic gearboxes, gearboxes of this kind are becoming obsolete in the last years of their existence, giving way to second-generation robotic transmissions.
Examples of cars with a robotic gearbox:
Peugeot 107/Citroen C1 (2-Tronic)
Opel Corsa 1.2 (EasyTronic)
Preselective gearbox
This is the "advanced robot". The name of each manufacturer, as a rule, is different, but the most common is DSG (Direct Shift Gearbox) of the German concern Volkswagen. The transmission is, as it were, two “boxes” of gear shifting assembled in one housing. One of them is engaged in switching even gears, the second is engaged in switching odd and reverse gears. Both are supposed to, in fact, on a separate clutch.
The trick is that in the preselective box, two gears are always on at the same time, only one clutch is closed, and the second closes as soon as the first opens. Moreover, this process takes a fraction of a second, providing an ultra-fast gear change and, at the same time, almost CVT smoothness.
Strangled, almost to the point of fainting, by the EURO-4,5,6 standards and so on, the engine began to produce torque in a very narrow rev range. Therefore, in order for the car to somehow accelerate and “ride”, the transmission needs to constantly turn on the gear that will definitely fall into the peak of thrust. And this can only be ensured by a large number of transmissions. And, although 8-speed automatic transmissions are already being used in series, designers are busy developing a 10-speed automatic transmission for cars.
No matter how many fans of the usual "mechanics", we can state with confidence that she did not have long to live. Automatic gearboxes have learned to shift gears with absolute comfort at a speed exceeding the blinking frequency of the human century, which means that there is less and less sense in the existence of a manual “box” ...
Every driver probably remembers the words of his first instructor. "Before turning the ignition key, make sure the car is in neutral." This article will discuss the types of gearboxes, their differences from each other, the advantages and disadvantages, as well as the scope.
On average, the crankshaft of the engines of most passenger cars has an operating speed of 800 to 8000 per minute. At the same time, peak power falls on four to five thousand revolutions. Of course, such a range of angular velocities does not meet the operating conditions of any wheeled vehicle in general and passenger cars in particular.
The main purpose of an automobile gearbox is to change the speed, as well as the torque transmitted from the engine crankshaft to the vehicle's drive wheels.
The first node of this kind was a manual transmission. There is an opinion that the word "mechanical" got into the name of the unit due to a misunderstood abbreviation adopted in the English-language technical literature. The letters MT stand for manual transmission, which means “manual, hand-switched transmission”, and not mechanical at all - mechanical.
How it works
It is easiest to explain the principle of operation of this unit using the example of a manual gearbox. In fact, the MCP is a multi-stage reduction gear, assembled according to a three-shaft, and less commonly, a two-shaft scheme. The input or drive shaft is connected to the engine flywheel by means of a clutch. The secondary or driven shaft has a rigid connection with the car's cardan shaft. The third, intermediate, shaft is necessary to transfer revolutions from the drive shaft to the driven one. The shafts are parallel to each other and assembled in a single housing. 
On the drive shaft is a gear that transmits movement to the intermediate shaft. The intermediate shaft is equipped with a block of dead-mounted gears, often made as a single unit. The driven shaft gears are located in the axle slots or special hubs. Between them are gear clutches that rotate with the shaft, but are able to move along its longitudinal axis. The gears and clutches of the driven shaft can interact with each other using gear rims on their end surfaces.
When you turn on any gear other than reverse, the clutch responsible for its inclusion is connected to the corresponding gear and blocks it. Moving as a whole, the driven shaft transfers rotation to the cardan shaft.
The forward movement of the clutch is reported by the driver of the vehicle, acting on it with the help of the gearshift handle, which interacts with the forks and sliders of the box.
Four-speed gearbox and its operation scheme
Highlighted in color:
- Input Shaft - Orange
- Secondary - yellow
- Intermediate - gray
Alphanumeric designations indicate the gear number and reverse.
Neutral position and first gear 
Five-speed gearbox
Video that demonstrates how it works.
Unsynchronized manual transmissions
The speeds of rotation of the gears of the driven shaft differ significantly from one another. In this case, when trying to change gear, the clutch simply cannot connect with the required gear, and the ring gear will be destroyed. To approximately equalize the speeds of rotation of the gear and the clutch, a technique called "double squeeze" is used. When shifting to a higher gear, the driver first depresses the clutch, then moves the shift lever to neutral. The intermediate shaft, and therefore the driven one, stops rotating. Then he releases the clutch, squeezes and engages the desired gear.
When switching from an upshift to a downshift, the driver needs to carry out similar manipulations, but at the moment when the box is turned off, you should press the accelerator pedal. This technique is called "double squeeze with regassing."
Non-synchronized manual gearboxes were used in passenger cars until the 1940s. Today they are used exclusively in sports cars, and here are the reasons:
- Faster switching speed than synchronized counterparts
- Better withstand high shock loads that occur during operation
Synchronized MCPs
These types of gearboxes are equipped with additional elements - synchronizers. The gears located on the driven shaft have a conical end surface. Between each gear and the shift clutch there is a bronze ring - a synchronizer. Starting the movement, the clutch picks up the ring and presses it against the end surface of the gear. Due to friction, the speed of rotation of the gear and the clutch are equalized, after which they are finally connected using a ring gear. To date, all modern cars that have a 4, 5 or 6-speed manual gearbox are equipped with synchronizers.
The history of the manual gearbox, from the Ford T to the Bugatti Veyron
Since the advent of the first car and to this day, designers have used the following types of manual gearboxes:
Automatic and semi-automatic transmissions
Despite the amazing capabilities of modern gearboxes, their design is based on the same time-tested manual gearbox. The changes affected the drive of the switching clutches and the method of transmitting torque from the engine crankshaft to the drive shaft of the box, otherwise the circuit remained unchanged.
Separately, there are devices called variators, their principle of operation will be considered separately.
An automatic transmission or automatic transmission consists of a torque converter and a conventional 5 or 6-speed manual gearbox. The role of the torque converter is to smoothly equalize the speeds of rotation of the drive and crankshafts. Upon reaching the desired speed, the lock-up clutch switches the torque converter into fluid clutch mode. The electronic control unit is responsible for the operation of the automatic transmission. 
The robotic gearbox is a manual transmission in which the gearshift and clutch disengagement functions are fully automated. The electronic control unit and electromechanical servos cope with the task no worse than a professional racer.
Comparative characteristics of types of gearboxes
Most neophytes choosing their first car are wondering - which box to choose? Mechanic or automatic. Or maybe a robot? Four-speed mechanics is not quoted, you need at least a five-speed gearbox. Or 7G Nronic.
Which gearbox is better depends solely on the operating conditions.
Automatic transmission has proven itself in city driving. 5 or 6-speed, providing a smooth ride of the car, relieving the driver from frequent gear changes while driving in the evening "toffee". There are instances with eight steps. But every comfort has its price. Increased fuel consumption and slow acceleration of the car are a moderate price to pay for the opportunity to relax on the way home.
Robotic boxes provide their owners with almost the same level of comfort. Fuel consumption is kept at the level of mechanics, but the response speed leaves much to be desired. Robots are made on the basis of modern 5 or 6-speed manual gearboxes. A great option for a city car and driving long distances on a smooth road.
The mechanical four-speed box of stars from the sky is not enough, but it perfectly fulfills its main purpose. Various types of 5 and 6-speed gearboxes will shake your nerves in the city, but they will show themselves perfectly on the highway, maintaining the optimal engine operation.
What is more important - comfort in the city or a mighty breakthrough on the highway, everyone must decide for himself.
The review contains the most popular automatic transmissions. We will tell you which machines to avoid, which problems are most common and which boxes are the most reliable.
The most reliable automatic transmissions
ZF 5HP 24/30.
- about 500,000 km.
The family of 5-speed automatics is designed for cars with a longitudinally mounted engine. The 5HP30 version appeared in 1992. It has found its application primarily in 8 and 12-cylinder BMW models. In addition, automatic transmission has found its wide application in Aston Martin, Bentley and Rolls-Royce. The box copes well with torque up to 560 Nm.
In 1996, the 5HP24 version was released, which was used in Jaguar and Range Rover. In 1997, a modification 5НР24А appeared, designed for vehicles with all-wheel drive. It was used in the Audi A6 and A8 with Quattro all-wheel drive and the Volkswagen Phaeton. The remaining boxes 5НР24/30 are designed only for vehicles with rear wheel drive.
The 5-speed ZF debunks the myth that a powerful engine drastically shortens the life of an automatic transmission. In the case of the 5HP series family, especially modifications 24 and 30, the boxes surely reach the milestone of 500,000 km, even in intensively used cars.
Application example :
Aston Martin DB7
BMW 5 E39, 7 E38, Z8
Jaguar XJ8
range rover
Rolls-Royce Silver Seraph
GM5L40-E.
Mileage to overhaul- about 450,000 km.
Since 1998, a 5-speed automatic transmission manufactured by GM has been installed in BMW cars - the first models of the 323i and 328i e46 series. Initially, it was intended for cars with a longitudinally mounted engine and rear-wheel drive. In 2000, a version for all-wheel drive modifications appeared, which immediately got into the BMW X5. In addition, since 2004, automatic transmission has been used in various rear-wheel drive GM models. The 5L40 is capable of handling up to 340 Nm of torque and is designed for vehicles weighing less than 1800 kg. The production of the machine ended in 2007. It was replaced by a 6-speed 6L50.
Durability is the main advantage of this transmission. The need for repairs usually arises no earlier than after 400-450 thousand km. The advantages include soft work.
Application example:
BMW 3 E46, 5 E39, X5 E53, Z3
Cadillac CTS, STS
Jeep 545R.F.E.
Mileage to overhaul- about 400,000 km.
The 5-speed automatic 545 RFE appeared in 2001. It was the next step in the evolution of the 45 RFE 4-speed automatic transmission, produced since 1999. The 545 was first used in the Jeep Grand Cherokee WJ, and later in other cars of this brand. For example, in Dodge pickups and even in London taxis.
Despite the fact that the box is used in cars that are subjected to heavy loads, it creates few problems. This is a typical representative of the American school: the shifts are very slow, but it is almost impossible to “drive in” the automatic transmission. Repair after 400,000 km is not very difficult.
Application example:
Jeep Grand Cherokee, Commander Wrangler
Dodge Dakota, Durango
ToyotaA340.
Mileage to overhaul- about 700,000 km.
The box is designed for cars with a front engine and rear or all-wheel drive. The transmission has 4 steps. A350 series - 5-speed. Automatic transmission has been offered since 1986.
The box is famous for its reliability and durability. At 300-400 thousand km, it may be necessary to replace worn clutches and oil seals. After a small repair, the box will last the same amount. The first overhaul may be needed only after 700,000 kilometers.
Application example:
Toyota 4Runner Supra
Lexus GS, LS
ToyotaA750.
Mileage to overhaul- about 500,000 km.
The 5-speed transmission was mainly used in large SUVs and SUVs of the Lexus and Toyota brands. It is still in production since 2003. The machine does not have a fast operating speed, but in terms of reliability it is one of the best. And this is despite the fact that the A750 is constantly working with heavy loads.
It is difficult to find an instance that would require a box repair up to 400,000 km. This is one of the few machines that you can rely on, even without knowing the car's past. It works equally well both on the first day after purchase, and after several hundred thousand kilometers.
Application example:
Toyota Land Cruiser
Lexus LX
Mercedes 722.4.
Mileage to overhaul- 700,000 km.
Today, no one produces such machines. The wear resistance of 722.4 has become legendary. The 4-speed gearbox has been used since the 1980s in Mercedes cars, including the 190 and W124. Regardless of the bundle - with a 4, 5 or 6-cylinder engine - it has always demonstrated high reliability.
The design of the machine 722.4 is practically indestructible. Problems can only arise in individual copies that have undergone extremely ruthless exploitation.
Application example:
Mercedes 190, 200-300 W124, C-class
JeepA904.
Mileage to overhaul- 600,000 km.
It must be admitted that the design of this transmission is archaic. The machine has only three gears, and it appeared in 1960. A904 is a modified version of the box from the 50s of the last century. Its production ended only in the 21st century. Agree, for 40 years they have not produced boxes that cause problems.
The endurance and durability of the automatic transmission is evidenced by the fact that it was used even in American trucks. Repair, thanks to a simple design, is not very complicated and may be needed only after 600,000 km.
Application example:
Jeep Cherokee XJ, Wrangler YJ, TJ
Mazda / Ford FN4A-EL / 4F27E.
Mileage to overhaul- 500,000 km.
The box was developed jointly by Mazda and Ford. In the cars of each of the companies, the machine received its own designation. Although the box was created relatively recently (in 2000), it has only 4 gears. But this is her only drawback. Gear changes are soft and smooth, and the torque converter can lock up over a wide rev range, helping to reduce fuel consumption. The most important advantage is that the box very rarely causes problems.
For both Ford and Mazda, 500,000 km before the 1st major automatic transmission repair is standard. Up to this point, there are practically no cases that require the intervention of service specialists.
Application example :
Ford Focus, Transit Connect
Mazda 3, Mazda 6
The most problematic automatic transmissions
aisinTF-80SC.
Repair cost- about 1500 $.
The classic six-speed automatic transmission is used in dozens of models from Alfa Romeo to Volvo. The engineers managed to create a compact box, in size, not exceeding the dimensions of a manual transmission. The design of the machine turned out to be light and modern. Time has shown that serious malfunctions do not happen with the box.
Regardless of the model, jerks are often observed when changing gears. The problem affects the 4th, 5th and 6th stages and is caused by improper operation of the solenoid valves in the valve body. Ignoring the problem may damage the box.
Application example:
Ford Mondeo
Peugeot 408
Opel Insignia
Volvo XC60
JatcoJF011E.
Repair cost- about 2500 $.
It is a continuously variable CVT transmission or CVT. The change in gear ratios occurs due to a smooth change in the position of the “belt” on the bevel wheels. Theoretically, such a box has many advantages. A virtually infinite number of gears allows you to keep the engine in the optimal operating range depending on current needs. This reduces fuel consumption. The change of gear ratios is imperceptible. There can be no talk of any pushes or jerks, which increases the level of comfort while driving. Due to its design, the variator has small dimensions and weight.
Unfortunately, often boxes of this type are criticized by drivers because of the unnatural mode of operation. They keep the engine rpm too high. During operation, the variator creates many problems.
The main element of the CVT is a steel belt, which wears out along with the cones. Repairs may cost about $2,500. Often the control module fails.
Application example:
Nissan Qashqai, X-Trail
Mitsubishi Outlander
AudiDL501.
Repair cost- up to 4000 $.
The commercial name of the S-Tronic box. It is an automated double clutch transmission (wet type) and is designed for models with engines mounted longitudinally with a maximum torque of 550 Nm. The box has 7 gears, and the range of gear ratios, depending on the engine, can reach 8:1.
Very often there are malfunctions in the mechatronics, which disables the clutch pack. Replacing the node does not solve the problem. Factory repair gives the best result, where they know how to correct design flaws.
Problems with the box occur regularly. Not all services are able to cope with its repair, the cost of which is very high.
Application example:
Audi A4, A5, Q5
ZF 6HP.
Repair cost- about 1500 $.
The first 6-speed automatic is used in many cars. It was first used in the 2001 BMW 7. Today it is installed in several dozen models. These are mainly premium cars or large SUVs. Automatic guarantees quick and smooth gear changes and practically does not increase fuel consumption.
There are several versions of the box, differing in size and ability to digest the maximum torque (up to 600 Nm). And this is where the problems begin. Such gigantic loads reduce the resource of any automatic transmission. And almost all cars with a ZF 6HP gearbox are equipped with high power engines.
Troubles arise, first of all, when paired with strong versions of engines. Often there are problems with 4th, 5th and 6th gears, which is caused by a rupture of the input shaft basket. In addition, malfunctions occur due to malfunctions in the electrical board of the box controller.
Application example:
BMW 3 E90, 5 E60, 7 E65, X5 E70
Jaguar XJ, XF
range rover
Volkswagen Phaeton
LUK 01J.
Repair cost– up to 5000 $.
The continuously variable automatic transmission developed jointly by LUK and Audi is commercially known as Multitronic. It is designed for cars with a longitudinally mounted engine and front-wheel drive. CVT is capable of digesting up to 400 Nm of torque. A chain is used instead of a steel belt.
Unfortunately, most owners have had a negative experience with the German CVT. A typical nuisance is that the car jerks at low speeds, even after choosing the neutral mode, and in the “D” position, the driving mode indicators flash.
Problems begin after 120-150 thousand km, and with an aggressive driving style - even earlier. The cost of repairs sometimes reaches $ 5,000, which is actually unprofitable. The most common cause of failure is wear on the drive chain and bevel gears. Often there are failures in the operation of the computer that controls the operation of the variator. The multitronic is also subject to mechanical damage. It can fail even as a result of a small collision.
Application example:
Audi A4, A5, A6.
aisinAW55-50.
Repair cost- about 1000 $.
This is one of the most common 5-speed automatic in stock cars. However, in different models, they have design differences, so they cannot be interchanged. One of the typical drawbacks is the constant twitching when switching from "N" to "D" and when starting off.
Fortunately, the box's great popularity and the limited range of recurring problems makes it quite easy for specialized services to troubleshoot. The cause of most ailments is the failure of the solenoid valves (comfortable switching, pressure lines, torque converter clutch) of the valve body. There are also leaks from the box radiator.
Application example :
Opel Vectra C
Renault Laguna
Volvo S40, V50, S60, V70
JatcoJF506E.
Repair cost- about 1500 $.
The classic 5-speed automatic transmission used in front-wheel drive models of many brands. The automatic machine in various models is distinguished by a torque converter and the selection of gear ratios.
Most often, malfunctions occur due to problems with the piston in one of the clutch packs. Another characteristic problem is the wear of solenoid valves. A typical repair will cost $1,500. The matter is complicated by the fact that the box requires a certain amount of experience from the mechanic. Otherwise, even changing the oil can damage the machine.
Application example :
Ford Mondeo
Land Rover Freelander
Mazda MPV
Volkswagen Golf Sharan
GM6T35/40/45.
Repair cost- about 2000 dollars.
The family of 6-speed automatics manufactured by GM is known as the Hydra-Matic. The box is designed for vehicles with a transverse engine. Different versions differ in their ability to transmit maximum torque.
There is only one main problem - the destruction of the wavy clamping spring. As a result, a large number of solid remains quickly disable the rest of the box. In this case, the cost of repairs reaches $ 2,000.
Application example:
Chevrolet Cruze, Malibu, Captiva.
Conclusion
The era of reliable and durable machines (with rare exceptions) ended at the turn of the century. Under the pretext of environmental concerns, the use of lead in electronic circuits was banned at that time. Lead-free solder joints are less strong, less reliable, and less resistant to corrosion. As a result, a large number of electronic malfunctions appeared, which in turn affected the durability of automatic transmissions. If the electronics fail, the elements of the box stop working under optimal conditions and are subject to accelerated wear.
What is better 4 steps or 6? which option is preferable?
The automatic is more massive than the mechanics, definitely heavier.
4 speed automatic
The first foreign car Solaris and the first machine in life. 4 speed. works with a slight delay. But how does it work. especially in kickdown mode. To overtake, it is enough to press the gas to the floor and the machine drops the gear or even two down. If 2nd gear is turned on, the interior is instantly filled with a roar, not only strong, but the sound is present, and it is beautiful. On the second car 3-4 seconds then a kick and 3rd gear. And it is very well chosen, it pulls well and the moment of 155 Newtons is available from 4000 rpm. Efficient acceleration. the third long gear and overtaking is very good on it. the car in this gear continues to accelerate to 170 mph! Then a cut-off at 6200. And the 4th gear is connected and there is sufficient traction on it. And the maximum speed of 180 declared is gained easily. And if the weather is not windy and the road is flat, then the car can be accelerated up to 200 km h.
I want to pay tribute to the fact that in this gearbox are selected very well. Of course the box is heavier than the mechanics but it is lighter than the 6 speed automatic. The transmission operates quietly and clearly without any hint of vibration. Are there any downsides to this box? Eat. Driving with a loaded trailer. Even a slight rise loads the engine in 4th gear and the box pokes third, but it’s worth letting off the gas a little and fourth turns on again, which in a moment goes back to third. But it's easy to decide. It is enough to include manual mode and third gear. The car will move at high engine speeds but will do it confidently up to 170 km / h. At the same time, the revolutions will certainly be 6200. The same thing on a mountain serpentine, the automatic mode revealed the shortcomings of long gears. It is hard for the motor and switching to preload occurs with a slight jerk. But again, when switching to manual mode, all this is eliminated. riding in a straight line with slight uphills is a real pleasure.
Engine speed at 120 km / h does not exceed 3000. And further acceleration does not fill the cabin with a roar. Even at 180 km / h in the cabin, you can talk calmly without tension, only rubber stands out in the noise. it is well heard. Fuel consumption with this box ranges from 7.5 liters per hundred to 9.5 depending on driving style. But this ride is dynamic. the maximum consumption at the same time at a speed of 180 km h is 16.5 liters per hundred. If you have to storm an off-road poorly passable area out of necessity. it is necessary to turn on 1 gear in manual mode, it is indicated on the selector - L. The car will not switch higher and there will be sufficient effort when overcoming the section and speed up to 50 km h is quite enough. Well, of course, the speed will be high, but a difficult-to-pass section of snow or mud can, of course, slip through with your mind so as not to tear anything off. To do this, I made a set of "Rural option" and "Nature" which help to secure in this matter and increase the cross-country ability of the car.
Here is an example of operation with a modified suspension. Solaris 1.6 sedan Automatic transmission 4 tbsp.
Now I will talk about the machine 6 tbsp. I'll be honest. It is more convenient than a four-mortar poker. Beautiful and sits comfortably in the hand. Movement forward and backward. No sectors. Manual mode is a very convenient lever to the left and manual mode with the display of gears on the on-board computer, unlike 4 mortars, here all 6 gears are full-fledged and can be switched on in manual mode. In the 4 mortar, only 1-2-3 gears could be fixed. now about the operation of the machine. This box is heavier than 4 mortars. Under the hood, it takes up more space. and the left side of the car is slightly lower than the right! Due to the greater mass of the box.
Another feature is a big vibration on the steering wheel. But this is possible due to a poor-quality long right wheel drive shaft. Vibration is felt from a speed of 90 km / h and is well manifested at 110 km / h. I don’t know how it is for anyone, but for me it is very noticeable and there is a difference with a 4-mortar where the steering wheel did not vibrate at all, unless there was an imbalance of the wheels. if they accelerate smoothly, the box switches imperceptibly, with almost no jerks. But in order to drive stably in 6th gear, you need to keep the speed within the aisles of 100-110 km / h at a lower speed and a small load, the fifth or even fourth gear is immediately tucked in. At the same time, the revolutions do not increase much, but there is no traction as current. rolls and rolls while fuel consumption is 8.5 -9 liters. If you drive dynamically. then the engine does not get out of the high turnover of 5 thousand is the norm. And it's very audible. Transmissions are frankly short and therefore they often get over. if you say the box tupit, no, it is quick with a slight delay, but the gears are selected in such a way that you don’t feel the pickup as such.
She switches but does not pull. Rather pulls kata by the tail, weak, sluggish acceleration. This is due to the fact that short gears do not allow the potential of the engine to be revealed in the maximum torque zone. There is too little time for this. Only a moment appears, and then a cut-off and pick-up already from high revs, where the traction aisle and further revs only reduce the torque. There is no pickup from here. Sluggish. Roaring despite the 6 gears and consumption I will say no less and even more than 4 mortars. Gasoline in the pipe! The power goes into the void. The engine, instead of pulling, dumps power on switching. and there are many. To go fast means the revolutions will be 5000-6000 thousand, and this is absolutely not noticeable by the acceleration thrust.
The roar of the engine and the small steps of the box do not make this box a driver's one, and the settings of the strangled Euro 5 generally endow top speed with paralysis. 180 km / h on the machine in general 6 speed is not included in the kickdown! This means that the car can only go to the maximum speed in 5th gear, while the engine speed is 5500! On the old box, 4th gear and 4500 rpm is much lower and quieter. Although the box is 4 steps. But there is an honest manual mode here and when it is turned on, you can also drive in 6th gear with lower speeds, but after 160 km / h the engine refuses to turn in 6th gear. The traction drops, the electronic collar suffocates like a wall. You turn on the fifth The car accelerates to 180 km / h, then it practically does not accelerate, it takes time. Having dispersed to 180 on the fifth, we turn on forcibly 6 and the car goes 180 for some time and then starts to lose traction, the speed drops and the gear in manual mode 6 does not switch gas, the full engine dies. Like a carburetor in which there is not enough gasoline.
The settings are stupid. Although the potential of the engine is. Probably strangled in favor of the requirement of euro 5. Well, she does not go, and here she will be given a head start by a 4-speed gearbox. About economy. I will say this if you drive on a flat road at 60-70 km h in calm weather, you can set a record for efficiency. and he is undeniable. 4.6 liters per 100 kilometers! But it's interesting how old the driver must be to move at such a speed, especially along the highway. If the speed is more than 80-90-100 and a slight pressure on the gas, then the flow rate is added up to 7-8 liters. And if the rises, then it easily exceeds 12-14 liters per hundred. The engine is strangled downshifts down the speed increases and fuel consumption increases. If you press down and disperse the car, the consumption will increase even more. The average fuel consumption in the summer is about 8.5 -9 liters per hundred. On a four-speed automatic 7-8.5 liters. Difference. If you drive in economy mode, then 6 mortar will be more economical.
But is the 6-speed automatic worse than its predecessor? Not certainly in that way. It is high-torque, so it is easier for him to pull a trailer. On the mountain serpentine, the shifts are softer without jerks and the gears are selected correctly, acceleration at low speeds is sufficient for overtaking. On long descents, you can easily pick up the gear in manual mode and the box effectively slows down without resorting to the main brakes. it is very comfortable on the descent with sharp turns and hairpins. gears engage clearly effectively slowing down. Movement in the mountains in manual mode is also very convenient. Short gears allow you to choose the right speed to keep the torque and have enough speed.
Summing up, I want to say. That a car with a 4-speed automatic is good with a 6-speed one as well. Each option has advantages and disadvantages.
The 4-speed is longer and tuned for maximum engine thrust capability. Hence, it is more playful, I would say capable of giving maximum acceleration for a long time of movement. Especially in the range from 100 to 160 mph. Fast set speed. This makes it possible to almost lightning-fast overtaking if necessary. This box allows you to reach the maximum declared speed of 180 km / h in maximum 4th gear and, under certain conditions, up to 200 km / h. The box is lighter than a 6 speed automatic. Wheel alignment is correct.
Disadvantages of this box Thoughtfulness under hard acceleration. Especially noticeable when driving for a long time in economy mode, sharp acceleration leads to a stupor for a couple of seconds. thinks then downshifts then accelerates. But it is worth entering the Kickdown mode. Traction and acceleration are followed up to the maximum possible speed. When the engine speed exceeds 4.5 thousand, the thrust gradually decreases, but the engine does not poke into the concrete wall and does not choke as intensely as at 6 speed. The disadvantage of a 4-speed gearbox is that under load, the shifts are sharper and the load on the engine is greater.
In the mountains, 4 gears are not enough, and long gears are harder to drive with constantly changing road conditions. Manual mode helps, but gear selection isn't great, and the difference matters. so it happens that the third one doesn’t pull, or rather it pulls but it’s hard and the second one doesn’t have enough speed, and if you drive faster, the speed is high again, the third one, but it’s a fast car accelerates, you need to slow down, and again the second and high speed. Same with the trailer. But the good thing is that the 1.6 engine is high-torque and can handle the load.
Can this box be improved? You can in terms of response, set it up for a faster response or add a sport mode. Adaptive mode slows down shifting speed too much.
Now consider the 6 speed box.
If you don’t drive fast and don’t resort to Kickdown, then efficiency is the strong point of this box, provided that you drive no more than 85 km / h. The consumption can be kept in the aisles of 5-5.5 liters per hundred on smooth asphalt. On a 4-speed automatic, the consumption is more than 6-6.5 liters. If you drive through the mountains or move under load, and even with a trailer. at low speeds, this box shows its muscularity, effortlessly selects the desired gear. And the car rolls briskly. Maximum acceleration range 60 - 110 mph. Further acceleration is more sluggish and after 160 acceleration is frankly slow and weak. turns out to be a sort of cargo horse. The box works well, but it is set up frankly unsuccessfully. It is configured to save the engine, but again, loading the engine less, it spins it much more than on a 4 mortar. And high engine speeds also wear it out.
A double-edged sword, and at the same time, consumption increases very much. Another minus the maximum speed is available only in 5th gear! What kind of economy can we talk about if the maximum speed of 180 km h is 5500. The movement of 120 km h at 2500 rpm in sixth is good! But the expense of 9-9.5 is a lot! cruising speed. I just threw the gas pedal, the traction drops instantly, as does the speed. A little added, the fifth one turns on already with a flow rate of 10-12 liters. A comfortable ride in the range of 110-130 km / h comes out at a flow rate of 8.5-9.5 liters per hundred, which is not a little.
With the same indicators, the consumption in a 4 mortar is less than a liter and a half. And most importantly, the 6-speed mortar does not want to go fast and frankly blunts at speed. The 6 gears that are available add extra weight and resistance to movement. more gears more friction surfaces. And what's more, 6th gear is made to save fuel; in fact, it only reduces engine speed at speeds up to 160 km/h. It does not save because the engine is loaded and even strangled. An example of a horse pulling a cart uphill. she needs to keep the rhythm and speed and instead the driver holds her. She is glad to pull out and the owner does not give from here the loss of strength and traction. less speed more strength is required to keep moving.
I think everything can be fixed. But adjust the brain in such a way that it is possible to select the mode of movement. It is necessary to configure the firmware of the engine and box. What would be the mode of full return. Flicked the toggle switch and transmission. 1-3-5-6 would shift in this sequence, without pinching in high gears. then the car will be able to go to maximum speed in 6th gear. And the acceleration thrust will be constant using the peak of the engine torque and not the cutoff stubs. Set up the engine and box. And the car will be gold. In the meantime, we eat what we have! Good luck to everyone, read the news and my articles. I hope you were able to learn a lot of interesting things and compare your feelings.
