Be sure to do a little research and come prepared to play with the particular CVT’s different modes and settings, as these can have a big impact on your perception of the transmission. Adjusting the diameter of one or both of those pulleys changes the ratio.Īs with any unfamiliar technology, we suggest you try before you buy, doing a thorough test drive of a CVT-equipped vehicle to make sure you’re comfortable with its behavior. This transmission has a pair of pulleys-one for the transmission’s input and one for its output-connected by a belt or chain. You might wonder what’s inside a CVT, if not gears. This negates some of the CVT’s efficiency advantage but addresses the auditory issues. Some will even mimic stepped gear changes on their own, either by default or in a certain mode. Many modern CVTs also allow the driver to “shift” through simulated gears, which are predetermined ratios the transmission moves between. The car uses this “first” gear for starting from a stop, improving response and acceleration, and then sends power through the continuously variable portion of the system, which manages ratios more efficiently.ĭrivers can treat a CVT as they would a traditional automatic, selecting drive and letting it do its job without further input. Toyota’s Dynamic-Shift CVT, offered in the Corolla sedan and hatchback, addresses these issues at least in part by including a distinct launch gear. Engines with a lot of torque, such as a V-6 or turbocharged four-cylinder, can minimize this issue, helping get the vehicle moving even when the ratio is not ideal. Acceleration can also feel sluggish, as it often takes a moment for the transmission to find the best ratio once you mash the pedal. Similarly, the drone of an engine at constant speed can be off-putting. Some find the lack of synchronization between the rise of engine speed and acceleration disconcerting. Under acceleration, a CVT’s smooth, stepless adjustment is accompanied by the sound of the engine revving up just once and staying there, then settling down once you back off the accelerator pedal. (Some automakers, knowing how much people hate change, have actually programmed CVTs to simulate those shifts more on that later.) Instead, the driver may hear the pitch of the engine change or nothing at all when the CVT alters its ratio. Because a CVT doesn't actually shift between fixed gear ratios, it avoids that jerk and telltale rev-pause-rev sequence. They’ll also hear a brief drop in powertrain sound as the engine slows for the shift, after which it resumes its audible climb toward higherRPM. With a traditional transmission, the driver often feels a subtle jerk as the car swaps gears. ![]() ![]() What is a CVT Transmission and what makes it different?Ī vehicle with a CVT sounds and feels different under acceleration than a vehicle with a conventional automatic. Because a CVT’s ratio adjustments are constant and don’t require the engine revs to fall like they do when a geared automatic shifts, the powertrain can remain at a sweet spot that either produces maximum power or uses the least amount of fuel necessary. The main advantage of this is improved fuel economy. More and more, automakers are replacing their traditional automatic transmissions with continuously variable transmissions, or CVTs, which, instead of shifting between fixed gear ratios, can vary their ratios infinitely within a range. CVTs are different than “regular” automatics.
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