Car reviews:. Up Next. They took the world of endurance racing by storm and pioneered many innovative technologies. How do aerodynamics affect fuel efficiency? Find a New Dealer. New Search. Find Near Me. Enter a Postal Code. We are currently experiencing technical difficulties. Please wait a few minutes and then try again. Back to Articles. CVT Transmission vs Automatic In conventional manual and automatic transmissions, a pre-set number of gears limits the powertrain to a narrow operational range where fuel efficiency and performance are somewhat limited.
Many drivers also miss the feel of the car shifting through the gears. Toyota listened to their drivers and made some exciting changes to their CVT. The new system will use a launch gear to give drivers the feel of a traditional transmission, and it will improve its efficiency in the lower gear ratios. This launch gear is just like the first gear in a regular transmission, and as the vehicle starts to speed up, it switches out and starts working as a normal CVT.
By using these fixed ratio gears, the new CVT will improve the belt efficiency and increase the shift speed ratio, resulting in better performance. Since the launch gear handles the highest input loads while the car gets up to speed, the equipment in the CVT has much less stress. CVTs, or continuously variable transmissions, have the advantage of being more fuel efficient than conventional automatics.
However, they've gained a bit of a bad reputation for their vague and disconnected feel. Most transmissions work by meshing physical gears to adjust the ratio between engine speed and wheel speed. A CVT does away with gears, instead using two conical pulleys connected with a belt. By changing the position of those pulleys, a CVT is able to constantly and continuously vary the drive ratio rather than stepping between fixed gears. In theory, a CVT can be always in the perfect "gear" for any combination of engine and road speeds, resulting in improved fuel economy relative to transmissions with fixed ratios.
There are, however, trade-offs. While more efficient most of the time, belt-driven CVTs can be less responsive when pulling away from a stop or passing and can be less efficient at very low speeds relative to geared transmissions. Drivers also tend to dislike the absence of perceptible shifting as well as the lag between throttle input and acceleration that poorly-tuned CVTs often exhibit. CVTs don't feature gears. Rather, a belt and adjustable pulleys are used to continuously vary the drive ratio.
This disconnected feel put even non-enthusiasts off of early CVTs, but the technology has been improved dramatically in recent-generation vehicles.
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