Continuously variable transmissions, otherwise popularly referred to as CVT, is a technology that has been around since the late 19th century, when it was it first introduced by Milton Reeves in 1879, and subsequently patented by Daimler and Benz in 1886. It has since evolved, and attracted much debate among car enthusiasts and manufacturers comparing it to the regular transmission system. At one time, it was derided as the shiftless transmission that forced drivers to keep revving up their engines for longer, just to shift their gears. It has also seen its fair share of drama, like back in 1994 when it was banned in formula one racing, for supposedly giving the best-funded teams an edge over the rest.
Lately, the automotive industry manufacturers like Mitsubishi, Ford, Nissan, Chevrolet, Audi and Toyota have been engineering some of their modern models with CVT transmissions. While many people feel that they are better compared to regular transmissions, some are still not convinced about their efficacy.
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So, what is the upside and downside of CVT transmission? To comprehensively explore this, it is important to understand the concept of continuously variable transmissions.
How CVT Works
A CVT transmission typically relies on varying diameter pulleys attached to a chain belt, consequently providing for a wide range of gears that you usually would not find in other transmission systems. While regular transmission systems rely on planetary gears that create a predictable gear ration pattern, CVT’s gear ratio persistently varies when the vehicle is being driven. Although specific performance levels are more dependent on the type of car you are driving, the overall efficacy is different compared to traditional transmissions.
Here are the various advantages and disadvantages of CVT transmission:
The Upside of CVT Transmission
One of the most annoying things about traditional transmissions isn’t a quality problem, it is the jerking when one is shifting the gears. Although this has been substantially reduced in modern cars, there is always some jerking, especially when you shift from parking to reverse gear. With CVT transmissions, however, the drive is usually smoother. As a matter of fact, some of the modern versions have eliminated this behavior. Drivers barely notice the gears shifting up or down.
Improved Fuel Efficiency
With the U.S government requiring automakers to double their fuel efficiency by the year 2025, this is certainly a major plus for CVT transmissions. According to the National Highway Traffic Safety Administration, a continuously variable transmission system reduces a car’s fuel usage by about 6%. That is because unlike traditional systems, the CVT usually varies the gear ratio according to the driving conditions.
Less Complexity Equals Fewer Quality Problems
Although we pride ourselves in modern cars relying on sophisticated, state of the art engines, they can be more complex to repair when quality problems arise. That is why CVT, which is considerably smaller, compact, and less complicated, is a favorite of some car mechanics when compared to conventional transmission systems. Theoretically, small and compact translates to fewer moving parts, which means reduced wear and repair.
The Downside of CVT Transmission
A standard CVT transmission system may not develop quality problems as often as a conventional system, but be prepared to cough up a lot of cash when repair is needed. Since they are usually tightly sealed, getting to the internal parts for diagnosis and repair can be a daunting task, particularly for mechanics who are already used to traditional transmissions. Finding a repair shop that is conversant with CVTs could be difficult, especially in rural areas.
Getting Used to the Feeling
This may be a minor disadvantage, but some drivers have reported having a hard time getting used to a CVT transmission, particularly ones who are used to conventional transmission systems. While it is easy to direct and control shifting with the rev in a conventional system, CVTs have a subtle and uniform rev that could consequently force you to press harder on the gas pedal. Additionally, if you are hypersensitive to noises, you may find the hum that comes from the belt a bit annoying. Unfortunately, manufacturers are yet to figure out a way to muffle this noise.
Overall, as you’ve possibly established already, the advantages of CVT transmission systems, by a large extent, outweigh its disadvantages. This, however, shouldn’t rule out the efficacy of conventional transmission systems. With both types of transmissions being effective, your choice, at the end of the day, depends on your individual driving preferences.
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