Difference between Automatic Transmission and Continuous Variable Transmission

While buying a car, one of the important things is to choose a transmission of the vehicle. Earlier when people think about transmission, they just have automatic to choose from, but today there is much more than that. With the advancement in technology, vehicles are equipped with more features. Today’s vehicles are equipped with the Continuous Variable Transmission, abbreviated as CVT.

automatic-transmission

Before starting, let’s know what transmission is. Transmission in a vehicle is a system of gears that transmit the power to the wheels generated by the engine. CVT is basically a type of automatic transmission only. CVT have the same control as those found for AT. While driving vehicles with ATs or CVTs, drivers do not have to manually shift gears. Vehicle’s computer system mechanizes the shifting. An Automatic Transmission (commonly “AT” or “Auto”) was invented in 1921 by Alfred Horner Munro of Regina. Automatic cars are popular as they have comparatively lesser wear and tear of parts and spares. On the other hand a CVT comprises of two pulleys joined together with a belt. Driving a car equipped with a CVT is more like an automatic. It increases the efficiency and power of the vehicle. Let’s understand more about the differences between these two.

  • Gear Ratios-
    Unlike AT, that has fixed number of gear ratios, generally 5-7, CVT has infinite number of gear ratios between minimum and maximum value to deliver the required amount of power for driving. There are two perpendicular pulleys connected via a V-belt. Both ends of the pulley i.e. top and bottom ends move apart and together concurrently, making sure that the distance between them and the length of the belt remain constant. Out of two pulleys, one is driven by the engine, and the other one is connected to the wheels. There are some CVTs that are chain operated which makes the price of the vehicle slightly more expensive to drive.

    AT have fixed number of gearbox while, CVT does not have a gearbox with set number of gears. Toothed wheels i.e., typical gear are also not used in CVT system. In CVT, there is a constant adjustment to the relationship between the engine speed and power transmitted to the wheels, so to avoid any extra use of fuel than required.

  • Fuel–Efficiency-
    In terms of fuel mileage, CVTs are extremely economical because in CVT, engine is kept within its most proficient operating range. While, Automatic transmissions come with a hydraulic torque converter which is externally cooled, unlike a clutch. Vehicles with CVT gives jerk free ride to persons in the vehicle. When it comes to providing efficient and smother ride, it is where CVT overtakes AT. In order to improve fuel efficiency many hybrids have CVTs in them. In non-hybrid models also makers are shifting towards CVTs.
  • Speed-
    With more efficient rpm, CVT reaches desired speed in minimum time period than AT. In AT, with higher speed, engine has to work harder. While in case of CVT, faster acceleration is provided at constant velocity hence engine does not have to work any harder.
  • Driving Pleasure-
    The difference between the driving experience of vehicles equipped with CVT and vehicles with AT is obvious for some people. For some, driving vehicles with a CVT is more lethargic, while for some it is fun. With AT one experiences the feel of driving a car, whereas it is missing in case of CVT. To give a feel of AT with benefits of CVT, automakers are working to give more feel like AT.

CVT lacks the facility of gear changes, a significant thing for people who enjoys gear changing. Some makers are providing a “sport” mode in their vehicles that programs CVT to simulate shifts. Some all terrain vehicles have CVTs in them.

When it comes to buying a vehicle people have specific preference. On comparing between CVT and AT it is obvious that vehicles with CVT are more fuel efficient and smoother to drive. But as CVT has complex system it is difficult to put out more torque than AT. There are plenty of CVTs and ATs equipped models available. Go and take a test drive to form your own opinion.

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2 thoughts on “Difference between Automatic Transmission and Continuous Variable Transmission

  1. Pingback: Difference between Automatic Transmission and Continuous Variable Transmission | JapaneseCarTrade.com

  2. Pingback: Which one to choose- Electric or Hybrid or Hydrogen or PHEV? | JapaneseCarTrade.com

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