As Car Engineer explains, the general public has been less accepting of the CVT due to the difference in noise perception from mechanical or step automatic transmission. CVTs can be expensive to repair or replace when compared to a conventional automatic transmission. Some of the common problems that owners run into include overheating, slipping, and sudden loss of acceleration.
Shuddering is also a common problem. Since CVTs depend on the belts to operate, if these suffer from excessive stretching or too much wear, the transmission can completely fail. According to Mister Transmission , while there are some advantages to having a CVT, traditional automatic transmissions also offer some benefits.
Like a CVT, an automatic transmission also has some downsides. 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. 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. Even basic maintenance often needs to be done by a trained mechanic. If the driver is willing to learn to utilize this transmission in the right way, then there are loads of benefits that await.
Increased fuel economy and efficient acceleration are the main draws of a CVT, but in order to make the most out of the transmission, a few considerations and practices must be followed. When accelerating, the transmission tends to mimic the behavior of a geared transmission. When going at full tilt you may notice the tachometer needle bouncing up and down the rev range.
You can also lock the gear ratio to engage in some engine brake to slow you down while descending from an incline. This is a classic case of manufacturers trying to meet the demands of car buyers who are used to traditional acceleration patterns in a car, but most CVTs are programmed to let the engine sit at an optimal rpm for the best acceleration given the throttle input. So the first actual tip that we have for you is to apply your throttle progressively.
The transmission is sensitive to small adjustments in the level of your throttle input. Since the transmission is progressive in its nature, throttle input must be done progressively as well. The transmission can jerk when taps are made abruptly.
This puts a little more stress on the transmission, which may cause some damage in a worst-case-scenario, otherwise the jerks are annoying. When you accelerate out of a stop, try to step on the gas slowly, so the car smoothly goes up to speed. 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.
Early CVT-equipped cars, such as those built by Dutch firm DAF, had a familiar whining noise as engine revs soared, but road speed built slowly. Today the latest CVT-equipped cars have plenty of sound proofing to ensure refinement is improved. Another quirk of the DAF system was that the cars it was fitted to didn't have a reverse gear, instead the CVT box simply worked in reverse, so in theory these cars had a top speed that was achievable going both backwards and forwards.
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