Honda CVT transmissionEnlarge Photo
And their flaws are completely different, which makes them each well-suited for some kinds of cars and ill-suited to others:
Dual-clutch automatics tend to offer snappy, coordinated shifts when you're driving quickly—and a little more driving enjoyment than a typical automatic—but at low speeds they're often not very well coordinated.
Continuously variable automatic transmissions (CVTs)—often considered the uninspiring alternatives—keep the engine in its sweet spot for acceleration (or fuel-efficiency) but often to the detriment of noise and vibration, leading to complaints of a disconnected, 'motorboating' feeling when accelerating—in which the note of the engine isn't connected to a sensation of speed. At their worst, CVT transmissions can feel sluggish, or as if something is uncertain or slipping.
CVTs at ten percent and growing
Among new vehicles with automatic transmissions, more than ten percent now have CVTs, and that percentage is growing each model year. That's because it's not just niche models; top-selling models like the Toyota Corolla, Honda Accord, and Honda Civic now have CVTs on their most popular models, as do family mainstays like the Subaru Outback and Forester.
“CVTs have proven that they work much better on mainstream vehicles,” said Jake Fisher, director of auto testing for Consumer Reports.
CVTs typically offer fuel-efficiency gains that are as big as those brought by eight- and nine-speed automatics, yet they cost less. That's part of the reason why Nissan—and CEO Carlos Ghosn—pursued them as a long-term commitment back when they were an unpopular option that few other automakers embraced in a big way.
It hasn’t exactly been a smooth road, either. Chrysler and Ford both tried CVTs in many of their vehicles, then backed away, with consumer acceptance part of it.
That commitment has proven a mixed bag over time for Nissan. The automaker has had some quality concerns and issues with perception for its CVTs, and most recently, Consumer Reports has seen some issues with the JATCO transmission in the Altima. “We currently don't recommend the Altima,” said Fisher, “And reliability—and the CVT—is part of it.”
Fisher thinks that CVTs are at a natural disadvantage against the latest and best automatic transmissions, and that it's mostly a perception issue, not an issue of performance.
CVTs rationally better, but lacking the driver connection
“With anything that follows fixed ratios, you have the direct connection,” he explained, and that makes the driver feel more satisfied and in control. “Across the board we’ve seen this—that the CVT improves fuel-efficiency, decreases satisfaction,” said Fisher.
And a number of automakers are finding ways to calibrate their CVTs in ways that restore that feeling of connectedness for the driver. For instance, recent CVTs in Honda, Subaru, and Toyota models will all 'catch' particular ratios during acceleration and follow them up the rev range—probably paying a very slightly penalty in efficiency or performance—in order to maintain more of a 'natural,' seat-of-the-pants feeling of acceleration.
Dissatisfaction with CVTs has, now and in the past, been less related to performance as it is to noise, Fisher says, and that's why some of the latest CVTs make slight sacrifices in performance in order to provide a more satisfying sound. The transmission in the Honda Accord is especially fairly impressive for that, he notes. “And really it’s a small price to pay for better noise characteristics.”