You'll also find that if a car is offered with a CVT gearbox, it will be more expensive than the same model with a manual gearbox, just like a regular auto. If you compared them back-to-back, the manual model would have better claimed fuel economy, too. The CVT gearbox, and variations thereof, has been around since the dawn of the motorcar, but it was the introduction of the Variomatic gearbox by Dutch car maker DAF in the s that saw CVT become more commonplace in cars.
A CVT gearbox has a relatively simple arrangement of two cone-shaped pulleys with a V-shaped drive belt connecting them.
One pulley is attached to the engine, while the other is joined to the wheels. When you press the accelerator, the engine revs and the cone moves according to the amount of power asked for. The other cone adjusts accordingly so that the drive belt maintains the same tension, and this is what determines how the car accelerates.
As the two cones move independently, that means there are no set gear ratios as you would find in a conventional auto or manual, so a CVT is, in effect, a single-speed unit with infinite gear ratios available. That also explains why CVT-equipped cars have a familiar high-revving character, because engine revs aren't related to wheel speed.
The change of speed is managed by the cone-pulley position change which is gradual and smooth. An easy visualisation is a set of two diametrically opposed cones, where the belt is always moving between the thick end and narrow end of the two cones to keep the engine in its optimum operating RPM revolutions per minute. This gives the desired acceleration and power whenever you need it. Hence, you get both superior performance and matchless comfort. In effect, a CVT has an unlimited number of gear ratios.
This means that the engine will always be running at the most efficient RPM, for any given speed. And since the engine is allowed to operate in the highest possible efficiency band, it delivers enhanced fuel efficiency in different driving conditions.
Some of these include:. How Stuff Works explains that an automatic transmission uses gear sets, a hydraulic system, and a torque converter. The hydraulic system regulates the bands and clutches that control the gear sets, and a pump pushes the transmission fluid through. The fluid pressure forces the shift valves to open and close, which opens different gear circuits.
Now you know the difference between a CVT transmission and an automatic transmission. Which one works for you? New Cars. Buyer's Guide. Type keyword s to search. Today's Top Stories. Future Cars Worth Waiting For: — Karl Tapales Getty Images. Advantages of CVT Depending on the vehicle and the driver, a CVT can provide a smoother driving experience when comparing it to a traditional automatic.
A flexible belt connects the two pulleys The width of the pulleys changes depending on how much power the vehicle needs. What Is Launch Gear? Disadvantages of CVT While the lack of upshifting and downshifting is considered an advantage of the CVT, some drivers miss the sensation of the vehicle moving through the shift points. There are limits on the engines that can work with a CVT in terms of power and size.
They don't last as long as a conventional transmission. CVTs are harder to work on. By continuing to use our site, you agree to our Terms of Service and Privacy Policy. Sign up. Main Menu Search driving. This advertisement has not loaded yet, but your article continues below.
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