Continuous Variable Gear Transmissions - which are reliable?

I understand the VW and also GM has tried continuous gear transaxles, and I'm wondering about test results and long-term reliability.

Are there particular implementations that people have found reliable and/or prefer as to performance?

Can such concepts be transferred to racing contexts?

On one lecture, I heard that the metal pulley was a weakness in the GM versions.

Snowmobiles have found them quite reliable for several years. Nissan also used a CVT in their Murano and I think a car as well. You might research the Nissan to see what kind of HP they were running through them and their reliability.

I had a Murano rental in Nevada with the CVT and AWD once. I was quite impressed with it. It was find driving through Las Vegas and always seemed to be where it should be for quick lane changes, etc. I also drove it on a 3 hour drive up to Tonapah, NV and up some off-road mountain passes through all sorts of weather (interestingly, the worst blizzard I've ever driven in was in NV in April while driving the Murano rental, and I'm from Iowa) and the CVT seemed to work well in all those situations.

-Rod

Wow I did a quick search of the Murano and discovered a horror story.

Apparently they fail within 50k, cost $6,000+ to fix, and Nissan refuses to warrantee them. Yikes!

Here's some sample statements from owners:

"A significant number of CVT and Front Transfer Case (cracks/fractures) issues from late models all the way up to my 2009.

"Nissan's Tom Naquin & Corporate were not helpful at all & blamed lack of oil change on my fractured Transfer Case. This - even after a loose electrical cable locked me on AWD for awhile a few months prior to this incident & my maintenance manual never mentioned any required oil changes per Schedules 1 & 2"

"We got rid of our 2004 Murano too. I was sad, because I really did like the vehicle. I filed a complaint with NTSB too, but so far no luck. I don't understand, Toyota issues a mass recall, but Nissan doesn't? The 2003 and 2004 Murano's have a known problem with the CVT and transfer case."

"Don't be fooled! Nissan is experiencing numerous problems with their CVT's but refuses to officially recall thevery defective transmission design. Nissan has taken an "arrogant" position on this issue. My '03 Murano SE has had been in the shop 3 times with CVT problems the last was a total failure. The cost was $6300"

"I had a tapping sound (thought it was a tire). It grew louder and became a banging sound. Took it to Nissan Dealer. I have 105,000 miles on my Nissan Murano AWD 2004.
They called and said my differential caused my transmission to go bad so they couldn't cover the repairs under the extended warranty. The estimate was $9400 for new transmission, transfer case and differential."

" I also have a 2004 Nissan Murano that I purchased December 2008......low mileage aprox. 33,000 miles. About 3 weeks it totally broke down on me....had to have it towed into the dealer and the diagnosis was damage to the Front Transfer Case. Since then, I have been battling with my extending warranty folks....still no luck. Total damages estimated thus far as $4800.....absolutlely ridiculous!!!!!!! "

"My Transfer Case components fractured at 72k mi. Nissan, w/ no investigation, concluded it was my fault for not changing the oil. I disagreed & complained to Nissan Consumer Affairs: 1) My '05-Manual does NOT even require oil change under Schedules 1&2 - confirmed by Kings Nissan. 2) A Naquin Tech mentioned running AWD on dry pavement is another potential cause. 3) A loose wire caused the SES & AWD light to stay-ON & vehicle would not run more than 20mph at 70k mi. (felt like trans/powertrain restricted)."

"It happened to me again a couple of weeks ago on my drive home at night. So scary! I was turning in an intersection and my car wouldn't react to my gas pedal. It hesitated, then lurched before finally catching up to speed. It's a miracle that I didn't get in an accident."

"Wow, can't believe how many Murano owners have the same problem...." From this blogsite:
HubPages: Nissan refuses... (http://perrya.hubpages.com/hub/Nissan-Refuses-to-Recall-Murano-Despite-Major-CVT-Problems)


Looks like Nissan's version of a Continuous Transmission is a dangerous FAIL....

Not sure how Nissan handles it, but I only see references to extended warranties, which are generally an aftermarket item.

If I recall, Daimler/Chrysler offered CVTs at some point. I recall hearing about a specific fluid in transmissions class.

Not sure how Nissan handles it, but I only see references to extended warranties, which are generally an aftermarket item.

If I recall, Daimler/Chrysler offered CVTs at some point. I recall hearing about a specific fluid in transmissions class.

Well, obviously a motor that slacks, then "surges" unpredicably is a crazy driving hazard, involving potential 'criminal neglegence causing death' episodes. This sounds more dangerous than say a powersteering failure, which only makes steering difficult...

Since I can't afford new cars, problems that only show up after 50,000 kilometers are pretty important to me.
Extended warrantees aren't an issue, but products that break down unpredictably and unlike other cars is a real panic button.

But even if there weren't a safety issue, any breakdown that potentially costs at least $6,000 is an automatic no-go.

I haven't ever paid over $2,000 for a car, and don't foresee ever being able to do so, so I don't want to buy something that costs three times my price range just to keep it on the road.

CVT's have been in Nissans and Honda's since the mid 90s.

Both companies started using them on low powered city cars as they could not handle high hp.
By the turn of the century however both we're using them on 2.0L DOHC engines, and holding around 180hp with out any trouble or reliability issues.

However, Honda have not yet gone further with adding them to high hp vechiles, and currently only fit them to the logo/fit/jazz/city and some models of the Civic in Japan.


Nissan are fitting them to many more vehicles in different markets, including several V6 power cars and soft roaders.

We get a lot of them sold here, second hand from Japan, and if serviced properly they are no less reliable than another gear box.



The think to remember with Nissans is they went totally broke in the late 90s and it took them until around 2003 to sort them selves out and get all new models to market.
During the time between going broke and replacing the model line up they often had to cut corners in order to cut costs.
As a result quality control took a hit and compromises were made.
Nothing I'm aware of that would affect safety, but deffinitly some things that affect vehicle life.

I'm not quite sure how the transfer case was causing transmissions to fail, but maybe it was putting a huge load on the transmission which in turn was causing the fluid to heat up and the transmission components to fail. What seems to be the common story with the complaints you found was that the transfer case seemed to be the source of the CVT failure. I'm not sure I'd condemn the CVT as unreliable if there is an outside force driving those failures.

I have absolutely no experience with the Murano outside of the rental I had for a few weeks, or any other CVT for that matter, I'm just suggesting you don't falsely associate transmission reliability with transfer case failure.

-Rod

It looks like Toyota also jumped on the CVT band wagon in the past few years, and Renault (through Nissan) have also been using them.

A search of used cars here shows plenty of Camry/Avalons and Corollas with CVT's, as well as Civics. Lots of Nissan Primeras of course, as well as the Murano and it's equivalents. Even found a Mitsubishi ASX.