— Every driver understands how a manual transmission differs from an automatic one, but the term “variator” began to be used relatively recently, so for many it is still not completely clear. How many gears does the CVT have? What's good about a variator? How to distinguish an automatic from a CVT? You will learn about this and much more from today’s article.
— A variator is a device that transmits traction from the engine to the wheels, capable of quite smoothly changing the speed at which the driven and driven disks rotate. CVTs are widely used in various scooters, snow scooters and jet skis. However, CVTs began to be actively used in cars only a few years ago.
— Before answering the question of which is better - a CVT or an automatic, it must be said that a CVT ensures smoother movement of the vehicle. During acceleration, only a slight noise is heard, which constantly increases. In most cases, a car with a CVT accelerates faster compared to models equipped with automatic transmission and manual transmission, since no time is wasted on switching gears. If we talk about who can reach a certain speed level faster, an automatic or a CVT, the latter is confidently in the lead.
— What is good about a variator compared to other types of transmission? A car with such a gearbox will not stall at the most inopportune moment. In addition, you will not roll down when climbing, so this option may be optimal for novice drivers.
— Some car enthusiasts do not like the fact that the variator makes a specific sound during operation, and it does not depend on the operating mode of the power unit. In addition, many car owners prefer to have a sporty “roar”, so the question of what to choose – a CVT or an automatic transmission – is irrelevant for them. However, this moment can hardly be called a significant “minus” of the variator, since it does not affect the speed performance of the car.
— This difference between a variator and an automatic transmission can even be called an advantage, since the electronics optimize the functioning of the engine, choosing the optimal option for its operation. If you really like conventional gearboxes, we recommend choosing the tiptronic option. This is a kind of gear shift emulator. CVTs are also equipped with an option that allows you to quickly change the engine gear ratio as a result of sharply pressing the accelerator pedal.
— This information should help you understand how a CVT differs from an automatic. But it is often very difficult to decide which is better, an automatic or a CVT in your case. Of course, a car with a CVT has serious advantages.
+ So, what is good about a variator:
• better acceleration;
• extending the life of the engine by optimizing the load; • economical fuel consumption; lower level of harmful emissions into the atmosphere; • less noisy operation compared to other gearboxes. — One gets the impression that the question “automatic or CVT” is not even worth discussing, but in fact, this type of transmission also has certain “cons” that also need to be taken into account.
— Disadvantages or “cons” of the variator:
1: A CVT, as a rule, is not installed on a car with powerful engines. 2: If the battery is disconnected for about 100 km, the CVT is automatically calibrated, which is necessary for its normal functioning. 3: Another difference between a variator and an automatic transmission is that it is filled with fluid, the cost of which significantly exceeds the cost of standard transmission oil. It cannot be replaced with an analogue from another machine model. 4: CVT repair is an expensive procedure that can only be performed by experienced craftsmen. 5: There are certain restrictions regarding towing a car with this transmission. 6: The variator can function correctly only if the different sensors show normal values. If at least one of these sensors breaks, many difficulties will arise, one of which is the incorrect operation of the variator.
What is an automatic transmission (AT)?
This gearbox belongs to the stepped planetary models, which are connected to the power plant using a torque converter. In this case, the process of selecting and shifting gears is carried out hydromechanically.
In modern models this is done electronically. It is this that determines the speed at which the box should operate at one time or another. At the same time, the number of steps is increasing all the time. If before this the standard solution was a four-stage unit, now cars are produced with models with 9 stages.
The main advantages of automatic transmission include the following:
- smooth gear changes;
- high degree of reliability;
- comfortable driving;
- gentle use of the engine and gearbox.
However, the automatic transmission has the following disadvantages:
- high price;
- high fuel consumption;
- high cost of repairs;
- the need for more time to accelerate;
- short service life;
- the impossibility of a “pusher” establishment.
Modern automatic transmissions have been greatly improved. There are models that are characterized by high reactivity. They are equipped with different operating modes - winter, sports, economical. In addition, the automatic transmission can have up to 8 gears.
Features of CVT driving
The CVT gearbox is designated by the Latin abbreviation CVT. In terms of its functionality, it is not much different from other checkpoints, but their operating principles are completely different. No shocks are felt when changing gears.
This happens because the diametrical plane of the driven and driving disks is corrected, and the machine accelerates smoothly, without shocks. The driver does not need to be distracted by changing the speed mode. Thanks to the automatic system, acceleration time is reduced and fuel is consumed more economically. The most optimal mode of the propulsion system is also selected automatically.
Even if the accelerator is completely “drowned”, the driver will not hear the sound that sports cars usually make. The excess load on the unit is removed using a smart electronic system.
What is a variator?
A variator also refers to an automatic transmission, but the principle of its operation is a smooth and continuous change in the gear ratio. It is important to consider that a continuously variable variator does not have the classic gear shift that a regular automatic transmission has.
As a result, the main difference for the driver is the freezing of engine speed, which is accompanied by a gradual increase in speed. There are no shocks at all during starting from a standstill and during acceleration.
The advantages of variators include:
- efficiency when using engine power;
- fuel economy;
- comfortable control and movement of the car;
- smooth running of the car;
- low load on the engine;
- environmental friendliness;
- smooth acceleration and rapid increase in speed;
- high efficiency.
However, the variator has the following disadvantages:
- complexity of design and repair;
- a limited number of services that can repair such a box;
- rapid wear when driving off-road;
- specific sounds during operation;
- limited period of operation;
- impossibility of installation on powerful cars.
Expert opinion
Karnaukh Ekaterina Vladimirovna
Graduated from the National University of Shipbuilding, majoring in Enterprise Economics
Experienced car enthusiasts and car mechanics do not recommend buying old cars with a CVT. If the purchase has been made, it is important to change the oil on time and monitor the fuel level.
Cannot be towed
The unit may suffer serious damage if a CVT-equipped vehicle is towed by another vehicle. By the way, when slipping, certain problems may also arise.
The vehicle's operating instructions provide an option for towing another vehicle. If this cannot be avoided, then towing should be carried out in strict accordance with the instructions. But even in this case, the possibility of breakdowns cannot be completely excluded. This is especially true for cars with significant mileage.
Slipping can also be dangerous. If the car is stuck in mud, it is better to give up trying to get out on your own, otherwise this may lead to wear on the spline joints. The gear life will also be significantly reduced. But repairing this unit can hit your pocket hard.
How to visually distinguish a CVT from an automatic?
Even experienced motorists do not always understand which gearbox is installed in the car. To visually determine its type, you need to follow a number of recommendations:
- Before inspecting the car, collect as much information as possible about the transmission options for a particular model. This can be done on the Internet or using technical literature and catalogs.
- Study the documents on the car and analyze the marking tables on the body and components. Typically, cars with an automatic transmission are supplemented with the designation “A” or “AT”. If a CVT is used, the abbreviation "CVT" is present.
- Visually inspect the gearshift lever. CVTs often have the designation “CVT”. It is also worth paying attention to the modes near the box shift selector. An ordinary machine, in addition to the standard PRND modes, has additional ones - “L”, “2”, and sometimes “3”. In this case, CVTs are equipped only with “L” mode.
However, many modern automatic transmissions, like CVTs, may not have the listed options. This means that they are complemented by PRND and M modes - tiptronic manual mode. This complicates the task somewhat. Therefore, at the next stage of checks, it is worth assessing the automatic transmission in motion, or analyzing the functions of the transmission while driving.
To do this, after starting the engine, you need to dynamically accelerate the car from a standstill in standard D mode. If during acceleration there is no noticeable gear shifting, and the engine operates equally at the same speed, this indicates the use of a variator. In the case of an automatic transmission, the car accelerates approximately the same as when using a manual transmission. This means that the engine first revs up, then shifts to a higher gear, after which the speed drops.
What is the difference between a CVT and an automatic?
The differences between an automatic and a CVT involve many features. They relate to design nuances, operating principles and other parameters.
Design
The automatic transmission is a standard torque converter, which was invented back in the early twentieth century. Modern models include the following components:
- Fluid couplings are required to ensure the transmission and conversion of torque that goes from the engine to the gearbox. This element is located on the flywheel of the power plant.
- Planetary gearbox – responsible for gear shifting and vehicle speed.
- Hydraulic control mechanism – controls the correct operation of the planetary gearbox.
The main elements of the variator are the following components:
- A device that is responsible for disconnecting the crankshaft and transmission.
- Torque converter.
- Control unit - its task is to control the transmission of torque and the acceleration process of the car.
- Automatic clutch mechanism.
- A special reverse unit and a planetary gearbox are required so that the machine can move backwards.
Principle of operation
The operation of an automatic transmission is carried out on the principle of transmitting torque, which comes from the crankshaft to other transmission mechanisms. All the pressure in such a transmission is provided by a hydraulic pump. A distinctive feature of the variator is the absence of gears. Therefore, there is no clear number of gears.
Reliability
The classic automatic is considered a more reliable option. It is more suitable for high speed driving, off-road driving, and aggressive driving style. In this case, the weak point of the variator is the belt. CVT is only suitable for smooth and careful driving.
Maintainability
Repairing a regular machine is much easier and cheaper. If the variator fails, you will have to spend a lot of money. In addition, not every master will undertake such work.
Price
Cars with a CVT are more affordable than cars that use an automatic transmission.
No need to load too much
When using a car with a CVT, it is highly not recommended to sharply increase the load - the increase should only be smooth, otherwise a visit to the service station cannot be avoided. This is a significant disadvantage of this mechanism, and this problem still remains unresolved. In cold weather, the variator must be warmed up, since the cooled oil will flow through the system very poorly, which is why some parts may be left without lubrication.
This operation must be performed as follows: the car is placed in “neutral” for a while (4-5 seconds is enough). This will help warm up the clutch slightly. You can move off only when the car is completely warmed up. At this moment, all elements of the gearbox have not yet fully warmed up, so it is not worth sharply increasing the speed for at least another kilometer after the start of movement. Even though the fuel consumption will be slightly higher, the driver will be able to save on replacing the gearbox, because the CVT model is a rather capricious thing and can easily break if used incorrectly.
The time for warming up the box directly depends on the air temperature - the lower it is, the longer it takes to warm up.
Experts recommend not to drive cars with manual transmission at all when the temperature drops to minus 35 degrees. But this is not always possible. If you happen to go on a trip in the cold, then you need to warm it up for at least half an hour, and the ride itself should take place in a gentle mode.
As you know, it is almost always cold in Finland, which is probably why an alternative method of warming up cars with manual transmission was invented there. There, some car models are equipped with special plugs, through which they are connected to the electrical network. This way the car warms up quickly. Such cars have characteristic cutouts on the bumpers.
comparison table
The main differences between the devices under consideration are summarized in the table:
| Criterion | Machine | Variable speed drive |
| Number of modes | Contains more modes. | Fewer modes are used - as a rule, “P”, “N”, “D”, “R”. |
| Designation | "AT" | "CVT" |
| Car behavior when driving | There are jerks and spots. | The movement is smoother. |
| Vehicle behavior when climbing a hill | If you brake and take your foot off the gas pedal, the car will continue to move smoothly forward without rolling back. | When braking while moving up, the car will roll back and will not move forward at idle. |
Summarize
Today, automatic transmissions are much more common than CVTs. But the latter has great potential. Automatic transmissions are more reliably used in cars with high power and capable of towing trailers. From the point of view of economy, a variator looks preferable.
CVT or automatic? The choice is yours. And it will depend on the characteristics of the devices that are your priority. Do you like smooth city driving in a small passenger car? Your choice is CVT. If you prefer sporty driving or often use a trailer, then an automatic is better for you.
