The continuously variable transmission (CVT) isn’t popular around these parts; we hate their attendant rubbery acceleration feel and the engine droning they cause. Still, their use is spreading wider than perhaps ever, with many automakers adopting them to increase their fuel-efficiency numbers in a hurry. (Whether CVTs are actually more efficient, well . . .) Nissan is one company that’s slurped from the CVT well most often, having offered them in nearly all of its vehicles for some time. We learned at the Tokyo auto show that it plans to debut its latest CVT in a front-wheel-drive vehicle next year. (We know that vehicle will be the 2013 Altima, although the company won’t officially admit it.)
The new version is said to improve fuel economy by up to 10 percent versus the previous generation, in part due to a claimed 40-percent reduction in friction. Its exterior casing is smaller by about 10 percent, and internal improvements include a new pulleys and a smaller oil pump that now uses lower-viscosity oil. Two variations of this Xtronic box will be made, including one for 2.0- to 2.5-liter applications and the other for engines ranging in displacement from 2.5- to 3.5 liters. Differences between the versions are limited to ratio spreads (7.0 in the smaller application, 6.3 in the larger) and a more robust belt in the 2.5-to-3.5-liter application to better handle the additional torque.
We briefly sampled the new CVT at Nissan’s Grandrive R&D track at the Oppama plant, outside Tokyo, Japan, and walked away with higher hopes for the future of rubber-band boxes. Installed in a current-gen Altima with a 270-hp, 3.5-liter V-6, the new CVT was significantly less irritating than usual, and we noticed a marked drop in engine noise. As an example, at 50 mph, the old transmission would hold 1500 rpm, while the new ‘box settled the V-6 in at just 1100 rpm. Off-the-line throttle response is quick thanks to a swifter torque-converter lockup (although that hurts smoothness and overall acceleration performance), and power seemed to be delivered upon request during at-speed passing maneuvers, without a drastic delay or a quick spike in engine rpm.
While we still prefer the feel of a traditional automatic to a CVT—and the control of a manual above all—we’re going to have to get used to seeing more of this type of transmission. If most new-generation CVTs can display the kind of advances we saw from this Nissan piece, we might even learn to tolerate them.
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