CVT Transmissions, Your Opinions?

bwb3 · #1 05-02-2013, 06:16 PM

We rented a Nissan Murano with a CVT transmission for a 350 mile trip, unfortunately to a family funeral. I was quite impressed with the performance. I know the CVT can't handle high horsepower but, what are your impressions? Reviews haven't been very kind.
The Murano was quite capable, good gas mileage, comfortable yet, firm seats, bad rear quarter blind spots.
Gene

processengr · #2 05-02-2013, 06:47 PM

From Honda, a functional description:
The CVT is comprised of a torque converter that drives two variable-width pulleys connected by a steel belt. With its angled inner faces, the belt can circle the angled pulley faces at varying diameter depending on the pulley width, which alters the effective ratio between the pulleys. Since there are no steps in the pulley faces, the range of possible gear ratios is essentially infinite. This ultra-fine control of the gear ratio is the key to the CVT's greater efficiency over a conventional automatic transmission with a limited number of discrete gear ratios. Instead of approximating the correct ratio for the conditions like a conventional automatic does, the Accord CVT can precisely select the optimum ratio from moment to moment without steps or slippage. "

The CVT can produce even better gas mileage than a manual transmission, assuming it is setup right. Not very sporting driving experience in most examples.
Some have a mode that the CVT can mimic a normal automatic transmission, but the exceptional fuel economy is lost. I personally think the CVTs are the way of the future...

wdb · #3 05-03-2013, 04:45 AM

I had a Maxima as a rental car a couple of years ago. 3.5L V6, CVT. It had plenty of horsepower. I really liked the transmission, in general, in that kind of car.

I consider cars like the Maxima to be ground-covering conveyances, not necessarily driven as much for pleasure as to simply get there and back again. Taken in that light the CVT Maxima was very nice. Push the gas and the revs go to ~3500 and sit there as the car accelerates. It's weird but in a cool way. The manual override was a bit too vague for my tastes but didn't really detract a lot from my enjoyment of the car.

I'd definitely consider a CVT in a car like the Murano or Maxima. In my STi there had better be a clutch pedal!

dcarrb · #4 05-03-2013, 05:04 AM

Consumer Reports tends to give Subaru products high marks, but they don't seem to think much of Subaru's CVT. Does Subaru even offer a conventional automatic anymore?

It probably won't be long until old-school manual transmissions are available only in a few models, as an added-cost option.

dcb

subeman90 · #5 05-03-2013, 05:17 AM

I'm ok with the CVT in my XV. I think it makes a low on HP engine seem faster and it really is very smooth. Now if this was a performance car no way but in daily grind driving this this is great. Towed a small trailer the other night with it too and it was wonderful.

processengr · #6 05-03-2013, 06:43 AM

Push the gas and the revs go to ~3500 and sit there as the car accelerates. It's weird but in a cool way.

This is referred to as the "rubber band effect" in regards to CVT(s) Not all do this. I have been driving a 2013 Accord with the CVT, for the most part it is un noticeable.

Gas mileage has been impressive, for a car this size. 29.5mpg average on my 52 mile daily commute, with 19 traffic lights and some steep hills. My SVX(s) average 20-21 mpg over the same commute.
Our 92 with the 4.44 averages 20 mpg using the odometer, but the speedometer is off ~6-8% high.

LetItSnow · #7 05-03-2013, 06:50 AM

The Altima I rented last month turned in some great fuel economy; I don't know how much of it was the CVT (the automatic on all 2013 Altimas). Fuel economy is one thing, but it sounded all sorts of sick and ugly, most notably on onramps.

As an indifferent commuter (if I was one), I'd be happy at the pumps. As a driving enthusiast (which I am), the thing makes me want to push it off a cliff.

Blacky · #8 05-03-2013, 06:53 AM

Quote:

Originally Posted by dcarrb

[I] Does Subaru even offer a conventional automatic anymore?
dcb

Yes they do. They are available with:
5-speed Electronic Direct Control Automatic Transmission with Manual Mode (5EAT)
Paddle shift controls
Straight shifter with shift position indicator on instrument panel
Lock-up torque converter
Transmission shift lock
Blipping control

From the Subaru Canada site.

svxcess · #9 05-03-2013, 07:10 AM

Our 2010 Outback, with CVT, is approaching 175,000 miles. It has preformed flawlessly during that time, giving smooth power and fantastic gas mileage,.

Once you get used to how the CVT operated, it becomes second nature. In Auto mode, it just spools up (much like a dimmer) and achieves its speed without the usual "shifts." If you mash the accelerator too quickly. the engine revs quickly at first and then the CVT catches up to it.

In manual mode, it will stay in any particular gear (there are 6) until you manually upshift with the paddled or console shifter. Same with downshifting.

Also in auto mode, if you are in D, anytime you can press the + or - shifter and it will temporarily shift into the corresponding gear and stay there as long as the accelerator is depressed. Once you release the accelerator, it goes back to D. I have been descending steep hills in Drive and used the - paddle shifter to slow me down, through engine braking.

As I said, totally problem-free so far. There is no place for you to add ATF and it is a sealed unit. Gas mileage has been fantastic. My average for my commute, highway and urban combined is a consistent 31.5-32 mpg, with the highest ever on our last trip ip South Carolina at over 36mpg. I assume that is because there is no lag and loss of power between shifts, as in a normal AT.

This was the very first CVT offered by Subaru and I am sure improvements have been made. The best of both world in this kind of car.

.

theflystyle · #10 05-03-2013, 08:14 AM

I didnt realize the CVT was a sealed unit. With all the other/older sealed transmissions I've dealt with (VW mostly) I wonder how they will hold up.

Tim · #11 05-03-2013, 08:37 AM

So if you floor a car with a CVT trans, would engine RPMs not reach redline?

dcarrb · #12 05-03-2013, 08:53 AM

As I recall, the Subaru Justy was one of the first cars to use a CVT, way back when. Reliability issues due to quality-control problems having to do with castings doomed it, and the experience seems to have scared Subaru away from the concept.

Someone told me awhile back that her mom's car had a sealed automatic transmission and I insisted, no way...

dcb

svxcess · #13 05-03-2013, 10:49 AM

Quote:

Originally Posted by Tim

So if you floor a car with a CVT trans, would engine RPMs not reach redline?

I would imagine there is some rev-limiting function. When I have done this, I think my revs were around 5,000 before the CVT catches up.

.

EdWindows · #14 05-03-2013, 11:44 AM

CVT's in cars are kinda iffy. I'd say they're a decent replacement for slushboxes, but they're best suited for ATV's and snowmobiles IMHO.

subeman90 · #15 05-03-2013, 12:17 PM

Quote:

Originally Posted by theflystyle

I didnt realize the CVT was a sealed unit. With all the other/older sealed transmissions I've dealt with (VW mostly) I wonder how they will hold up.

according to my owners manual there is a place to put fluid in and take it out. It needs to be on a computer to do this (dealer) and there is a service interval if used under "severe duty".

I was told the fluid is wicked expensive too!

Oh and I have seen some regular automatics that are "sealed units" no thanks.