Nissan Rogue Forum

The Xtronic CVT differs from conventional automatic transmissions by featuring an infinitely variable gear ratio between its lowest and highest gears. Whereas a traditional automatic transmission typically makes large ratio jumps from one static gear to the next, the Xtronic CVT flows smoothly by transitioning through gear ratios with the feel of one perfectly calibrated gear.

The latest, third-generation Xtronic CVT retunes a number of features to improve performance, including the use of a smaller, more efficient oil pump; the adoption of a compact chain drive for 2.0-liter engine applications (which reduces the transmission size as a whole); and improvement of the precision of the pulley diameter control, allowing for more efficient belt pressure, more reliable torque transfer and improved fuel economy.

“Across the industry, manufacturers are sacrificing performance for efficiency and economy,” said Bill Bosley, vice president and general manager, Nissan Division. “But we refuse to detract from the Nissan driving experience. The expanded use of our advanced Xtronic CVT is the ideal way to offer sporty performance and fuel efficiency in one package.”
How Xtronic CVT Works While automatic and manual transmissions use multiple gear sets with an integral clutch and bands to achieve separate gear ratios, Xtronic CVT uses an infinitely adjustable ratio design. For example, instead of jumping from a 2nd gear ratio of 1.950 to a 3rd gear ratio of 1.392, Xtronic CVT can rapidly progress through 1.950, 1.949, 1.948 - stepping seamlessly through 1.392 as the diameter of its pulleys gradually adjust. Because of this progression, the Xtronic CVT “changes” ratios with no perceptible pauses, jerks or lurches, virtually eliminating traditional shift shock.

Each pulley is composed of two stout cones, each point facing the other, similar to a yo-yo. A steel belt with a V-shaped cross section connects the cones. As the engine speed increases, the cones of the drive pulley slowly come together, gradually pushing the belt further from the pulley’s axis. Simultaneously, the driven pulley’s cones are moving farther apart, easing the belt closer to the axis of the driven pulley.

The pulleys are controlled to proportionately expand and contract so the ratio of the drive diameters between the two pulleys can be varied over a wide range. The Xtronic CVT offers a spread of “gear” ratios between its lowest and highest range (2.371:1 to 0.439:1 for the 3.5-liter V6 engine; 2.349:1 to 0.394:1 for the 2.5-liter 4-cylinder engine; 2.349:1 to 0.394:1 for the 2.0-liter 4-cylinder engine and 2.561:1 to 0.427:1 for the 1.5-liter through 1.8-liter 4-cylinder engines).

At the heart of the Xtronic CVT is a high-strength, flexible steel belt. The strength of this belt enables the transmission to handle a high amount of torque input, fitting for multiple sizes, displacements and power levels of different Nissan engines.

Xtronic CVT offers a number of benefits over traditional automatic or manual transmissions. The most obvious benefit is the smooth ratio changes, versus the “clunk” of a shifting transmission that is familiar to most drivers. In eliminating these “steps,” the Xtronic CVT allows the engine to run closer to its optimal rpm, rather than dipping below or working above it like an automatic or manual transmission. By maintaining ideal engine speed and avoiding unnecessary engine rpm, the Xtronic CVT optimizes fuel economy and emissions performance.

For additional fuel economy, Xtronic CVT offers an expanded torque converter lockup range. While a conventional automatic transmission locks up in the mid-to-high speed range, a traditional CVT transmission only benefits from the torque converter at startup. Recognizing this, Nissan engineered the Xtronic CVT torque converter with a lockup range that extends further into lower speeds, allowing for a better range of manual-transmission-like direct transfer of efficient engine power.
Additionally, Xtronic CVT has numerous other advantages over conventional CVT transmissions. Xtronic CVT boasts a wider gear ratio, which allows for improvements in both performance and economy. And, thanks to smaller minimum drive pulley radius, Xtronic CVT delivers better acceleration performance than traditional CVTs, and its smaller minimum driven pulley radius allows for better fuel economy.

Attached Files

rogue cvt.pdf (346.9 KB, 35 views)

For an excellent video to see one, cut open, in action, check out this video.

Unfortunately, the text is Japanese, not English, but oen should definitely get an understanding of steel belt CVT operation based on viewing this (this does not go into toroidal CVTs, which are a completely different topic all together).

-Ed

Very informative links, guys. Thanks!

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2008 Nissan Rogue SL, AWD, Venom Red, Black Leather Pkg, Prem Pkg, bumper protector, splash guards, floor mats

Squid - that was the best article I have read so far on the CVT - thanks for posting. I do have issues with the shift point or the gear ratio at between 30 and 40 mph where the rpm's drop to like 1200 rpm's and the car lugs before it picks up and pass the 40 mph range. I wish Nissan would address that. I won't go into what is right or wrong here - I got hammer by so loyal Nissan owners in another forum - just know it is a issue with alot of folks and thought maybe Nissan might have addressed it by now. Any again thanks for your informative article....

Attached Images

IMG_0004.jpg (350.2 KB, 5 views)

I'd like to hear your thoughts and I'm sure I'm not alone so fire away.

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Please Click for Sarah's Wish

Like he said, he has been shaked a little bit on another forum from the same affirmation, so I don't see the point of bashing him again here.

That is his opinion, and like the joke said: he agrees with himself.

For my part, I don't see this "lug" as an inconvenient as he mainly see the benefit of it: better fuel economy.

But we probably don't have the same background which could explain our different opinion on this: I always drove 4 cylinders cars with manual shift, so I am used to lug sometimes the engine (but I am not as good as the CVT programming).

I think we are still allowed to not agree with someone else, right?

Hey Pescakl1 - not really shaken - suprised maybe by the reaction of some people. I don't think going into this again will solve or change anyone's mind. I just wanted to express my thoughts and feeling on this - I still don't think it is right and feel the manufacture could improve the virtual shift point with a tiny software adjustment. Is it going to change my feeling for the car or how I still have fun driving it - No.

i agree 100% = its for mpg's , but it certainly is a royal pain in the a55 when trying to take off from a light where 2 lanes merge into 1.
-good luck being the 1st or second; i feel even priuses in hybrid mode, towing a cruise liner boat, with a fat sumo wrestler behind the wheel- running on one 9v battery could beat me - UNLESS IM ALMOST FLOORING THE PEDAL. if i floor the rogue, then it takes off like a screaming bat out of h3ll