Continuos Variable Transmissions

[William_Cannon 86]

Anyone own a car with one? Thoughts on them?

 

I don’t know if I could get used to a shiftless car but also don’t know it would be much different than a 9 or 10 speed automatic.

[Heisenberg 162]

I've got a '16 Subaru with a CVT.  At ~80,000 miles there have been no issues.

[52-80 19162]

they can behave differently depending on the programming.  most implementations like nissans are terribly rubberband feeling.  hyundai makes their mimic traditional autos and you cant really tell its cvt

[GottaB 594]

My accord has one I think. I really like it.

[Liquor and Poker 3659]

8 minutes ago, GottaB said:

My accord has one I think. I really like it.

OK-wait.  I can see not caring or saying it’s fine or even enjoying not thinking about it, but please explain why you actually “like” a CVT.   I’ve never heard that before. 

To answer the OP,  what do you want to know?   I personally despise them- they are legthargic and slow, loud, unresponsive, they have no low torque, and they make you feel like you’re driving in a simulator.  And when they break a CVT it tends to be even more expensive to fix them.   I’d drive a 8-10 speed auto all day over one.  

But if gas mileage is key to you, they are generally the way to go.  For the same reason, they tend to be mated with smaller I-4 motors. And if your vehicle is purely a utilitarian way to get things and people to places, I guess they’re fine.   You can kind of think of it as cruise control for the transmission, but on all the time.

The fact that you know what one is makes me think you probably won’t like it.  Most people who are fine with them have never even heard of them- it’s the transmission for people who really don’t want to think about how their car works. If road feel from a tighter suspension is an annoyance to you, and you couldn’t care less about things like steering response, a CVT is a fully acceptable choice.

Lore wise, Nissan’s are historically known to be more problematic, but I’m not sure that’s still really true.  Hondas are known to be the “smoothest” and Mitsubishis are the loudest.  

As with all things car, though, take one for a test drive and see for yourself.  

[TwiceHorn 31493]

1 minute ago, Liquor and Poker said:

OK-wait.  I can see not caring or saying it’s fine or even enjoying not thinking about it, but please explain why you actually “like” a CVT.   I’ve never heard that before. 

To answer the OP,  what do you want to know?   I personally despise them- they are legthargic and slow, loud, unresponsive, they have no low torque, and they make you feel like you’re driving in a simulator.  And when they break a CVT it tends to be even more expensive to fix them.   I’d drive a 8-10 speed auto all day over one.  

But if gas mileage is key to you, they are generally the way to go.  For the same reason, they tend to be mated with smaller I-4 motors. And if your vehicle is purely a utilitarian way to get things and people to places, I guess they’re fine.   You can kind of think of it as cruise control for the transmission, but on all the time.

The fact that you know what one is makes me think you probably won’t like it.  Most people who are fine with them have never even heard of them- it’s the transmission for people who really don’t want to think about how their car works. If road feel from a tighter suspension is an annoyance to you, and you couldn’t care less about things like steering response, a CVT is a fully acceptable choice.

Lore wise, Nissan’s are historically known to be more problematic, but I’m not sure that’s still really true.  Hondas are known to be the “smoothest” and Mitsubishis are the loudest.  

As with all things car, though, take one for a test drive and see for yourself.  

This is a pretty solid post on them.

Look at GottaB, not even sure he has a CVT.

They were quite problematic in the early going, but that seems to have been sorted out.

Definitely not for the enthusiast, most likely.

[torre 1286]

Agree with Twice,  solid post by L&P.

In the market for a vehicle,  I have read numerous articles on CVTs.  Link below.   As L&P states,  some  make better  than others.   Probably can't expect the overall longetivity with a CVT,  but most new vehicles with a regular transmission are going to the 8 or 10 speed for gas mileage and some also have issues.

 

 

https://www.carfax.com/blog/CVT-pros-and-cons

 

 

[Armybrat 40850]

6 hours ago, GottaB said:

My accord has one I think. I really like it.

Same here.

[GottaB 594]

OK-wait.  I can see not caring or saying it’s fine or even enjoying not thinking about it, but please explain why you actually “like” a CVT.   I’ve never heard that before. 

To answer the OP,  what do you want to know?   I personally despise them- they are legthargic and slow, loud, unresponsive, they have no low torque, and they make you feel like you’re driving in a simulator.  And when they break a CVT it tends to be even more expensive to fix them.   I’d drive a 8-10 speed auto all day over one.  
But if gas mileage is key to you, they are generally the way to go.  For the same reason, they tend to be mated with smaller I-4 motors. And if your vehicle is purely a utilitarian way to get things and people to places, I guess they’re fine.   You can kind of think of it as cruise control for the transmission, but on all the time.
The fact that you know what one is makes me think you probably won’t like it.  Most people who are fine with them have never even heard of them- it’s the transmission for people who really don’t want to think about how their car works. If road feel from a tighter suspension is an annoyance to you, and you couldn’t care less about things like steering response, a CVT is a fully acceptable choice.
Lore wise, Nissan’s are historically known to be more problematic, but I’m not sure that’s still really true.  Hondas are known to be the “smoothest” and Mitsubishis are the loudest.  

As with all things car, though, take one for a test drive and see for yourself.  

I verified. I have a 2.4 L I4 CVT. like it because it’s smooth and has good pick up when I take off at a light. There is a mimicked gear change but it happens at a point past where my other automatics would happen so I’m going faster than it feels like.

Beyond that I never notice it except when I jump in my wife’s car and notice all the gear changes.

[XYZ 2154]

I like CVTs better than slushboxes. I’ve driven three Prii, a Ford Fusion Hybrid, and two Foresters. The Subaru implementation is the least good of the ones I’ve driven (they are programmed to “shift”, kind of, which is stupid), but it’s still better than the previous generation slushbox.

[TwiceHorn 31493]

One thing I have always wondered about with CVTs is slip.  There's got to be some slip in a transmission for it to operate correctly.  Slip meaning the input shaft turns without a corresponding rotation of the output shaft.

The fluid coupling of a conventional, "slushbox" AT (torque converter) is all about slip and is inherently well-configured to deal with the heat and friction generated (the slip mostly occurs in the fluid, which circulates around and can even be cooled by a radiator).

A manual transmission uses clutch plates, which, like brakes, are decently suited to handling the heat and friction and slip should be minimized (don't ride the clutch!).

I'm not sure about dual-clutch (PDK) transmissions.  They use plates also, I believe, but they're smaller than a conventional clutch, but I also think they do their damndest to avoid slip.  This may be why they're reserved mostly for expensive performance cars and may still be troublesome.

On the other hand, the belt and pulley thing of a CVT has to slip some, I think, and the configuration of the components does not seem well suited to dissipating or dealing with the heat, especially the belt.  Also, in addition to slip (the rotation of one pulley relative to another not constrained by the belt), it seems like there's a lot of friction inherent in "changing gears" or moving the belt. and unlike transmission slip, is occurring most all the time.**

This is an intuitive engineering analysis, not a quantitative one, obviously, and I'm sure the engineers have it worked out.  But it seems like kind of an inherent weakness in the design.

**question:  for those CVTs that have "shift points," is that something that happens say during acceleration then it reverts to continuous operation, or do the pulleys stay locked in "gears" or set ratios?

Edited May 5, 2020 by TwiceHorn

[Dbeasy 15066]

Honda has gone from one of the highest quality vehicle brands in the world to one of the worst in the last few years. I may have this wrong, but I vaguely recall articles referencing CVT as one of the main reasons why.

[ShaggyBevo RIP 3868]

1 hour ago, XYZ said:

I like CVTs better than slushboxes. I’ve driven three Prii, a Ford Fusion Hybrid, and two Foresters. The Subaru implementation is the least good of the ones I’ve driven (they are programmed to “shift”, kind of, which is stupid), but it’s still better than the previous generation slushbox.

Everyone complained about CVTs not feeling like a traditional transmission so Subaru put in fake shift points to imitate a traditional transmission. Now people are complaining about the 'shift' points.  If you use you cruise control acc function Subies don't fake shift.

The Subaru Ascent uses one and it has its full torque available at 2000rpm. No other SUV/CUV in its size class can match that regardless of which transmission.

And yes it is true to stay away from anything with a Jatco(Nissan) CVT in it.

[TwiceHorn 31493]

33 minutes ago, Dbeasy said:

Honda has gone from one of the highest quality vehicle brands in the world to one of the worst in the last few years. I may have this wrong, but I vaguely recall articles referencing CVT as one of the main reasons why.

I'm not sure they're one of the worst, but definitely slipped.  And yes, I think CVT, as well as trying to keep up with the 8-9-10 speed transmissions has been an issue for them.  Transmissions have been a weak point for Honda, historically.

[dingleberryswitzer 2724]

3 hours ago, TwiceHorn said:

On the other hand, the belt and pulley thing of a CVT has to slip some, I think, and the configuration of the components does not seem well suited to dissipating or dealing with the heat, especially the belt.  Also, in addition to slip (the rotation of one pulley relative to another not constrained by the belt), it seems like there's a lot of friction inherent in "changing gears" or moving the belt. and unlike transmission slip, is occurring most all the time

I think they use either a torque converter or some sort of electronic controlled clutch.  

[TwiceHorn 31493]

9 minutes ago, dingleberryswitzer said:

I think they use either a torque converter or some sort of electronic controlled clutch.  

Aha.  Don't think they'd use a torque converter because that would be too sloppy and eliminate the "100% torque transmission" selling point, but a slip point/clutch somewhere other than the pulleys and belts makes sense.

[Dbeasy 15066]

3 hours ago, TwiceHorn said:

I'm not sure they're one of the worst, but definitely slipped.  And yes, I think CVT, as well as trying to keep up with the 8-9-10 speed transmissions has been an issue for them.  Transmissions have been a weak point for Honda, historically.

Yes, Honda only dropped to 12th out of 30th car brands. I was thinking of Acura, which dropped to 28th out of 30 in Consumer Reports rankings this year. Shocking.

[William_Cannon 86]

.. 

 

To answer the OP,  what do you want to know?   I personally despise them- they are legthargic and slow, loud, unresponsive, they have no low torque, and they make you feel like you’re driving in a simulator.   

 

As with all things car, though, take one for a test drive and see for yourself.  

 

I don’t know much but was reading on another forum about them since I’m considering buying a sedan. It’s to be determined how much I’ll actually drive it and therefore how much I should care and if I want to pay extra for a regular tranny. However, I wanted to have a basic understanding of pros and cons in preparation of any potential fire sales. And yeah I need to test drive...

[ShaggyBevo RIP 3868]

20 hours ago, TwiceHorn said:

I'm not sure they're one of the worst, but definitely slipped.  And yes, I think CVT, as well as trying to keep up with the 8-9-10 speed transmissions has been an issue for them.  Transmissions have been a weak point for Honda, historically.

It Honda 8-9-10 speed transmissions that has been Honda's issue not their CVTs.

[ShaggyBevo RIP 3868]

14 hours ago, William_Cannon said:

 

I don’t know much but was reading on another forum about them since I’m considering buying a sedan. It’s to be determined how much I’ll actually drive it and therefore how much I should care and if I want to pay extra for a regular tranny. However, I wanted to have a basic understanding of pros and cons in preparation of any potential fire sales. And yeah I need to test drive...

Finding a sedan without a CVT is soon going to be akin to trying to find one with manual shifting.

Here is a list of some of the 2020s with CVTs.

• Buick: Encore GX
• Chevrolet: Malibu, Spark
• Ford: Escape Hybrid, Escape plug-in hybrid, Fusion Energi (plug-in hybrid), Fusion Hybrid
• Honda: Accord, Accord Hybrid, Civic, Clarity Plug-in Hybrid, CR-V, Fit, HR-V, Insight
• Hyundai: Accent, Elantra, Venue
• Infiniti: QX50, QX60
• Kia: Forte, Rio, Soul
• Lexus: ES 300h, NX 300h, RX 450h, RX 450hL, UX 250h
• Lincoln: MKX Hybrid
• Mitsubishi: Eclipse Cross, Mirage, Mirage G4, Outlander, Outlander Sport
• Nissan: Altima, Kicks, Maxima, Murano, NV200, Pathfinder, Rogue, Rogue Sport, Sentra, Versa
• Subaru: Ascent, Crosstrek, Crosstrek Hybrid, Forester, Impreza, Legacy, Outback
• Toyota: Avalon Hybrid, C-HR, Camry Hybrid, Corolla, Corolla Hybrid, Highlander Hybrid, Prius, Prius Prime (plug-in hybrid), RAV4 Hybrid

 

Edited May 6, 2020 by ShaggyBevo RIP

[ShaggyBevo RIP 3868]

More complete list here- https://en.wikipedia.org/wiki/List_of_automobiles_with_continuously_variable_transmissions

[dingleberryswitzer 2724]

4 hours ago, ShaggyBevo RIP said:

Finding a sedan without a CVT is soon going to be akin to trying to find one with manual shifting

I'm waiting for a car with a cvt that you can manually select the ratio.  I believe a few years ago (and maybe still not) Subaru WRX's could be had with a CVT with paddle shifters that mimicked a 6 speed.  

[XYZ 2154]

1 hour ago, dingleberryswitzer said:

I'm waiting for a car with a cvt that you can manually select the ratio.  I believe a few years ago (and maybe still not) Subaru WRX's could be had with a CVT with paddle shifters that mimicked a 6 speed.  

My 2015 Subaru Forester had that. It was a CVT but you could put it in manual mode and “shift” with paddles. There was one configuration with 6 “gears” and another with 8.

[ShaggyBevo RIP 3868]

On 5/6/2020 at 2:08 PM, dingleberryswitzer said:

I'm waiting for a car with a cvt that you can manually select the ratio.  I believe a few years ago (and maybe still not) Subaru WRX's could be had with a CVT with paddle shifters that mimicked a 6 speed.  

Most of the present day Subarus with CVTs have paddles. Some of the hyper-milers claim they get better MPGs using the paddles.

 

Edited May 7, 2020 by ShaggyBevo RIP