Mazda- CVT's are not good for high speed - huh?

[buster]

Quote:
CVTs are not good for high speed, or for direct feel or quick response, so we ruled CVTs out right away,


Don't tell that to Subaru.

http://www.carreviewsoup.com/mazda3-reaches-for-the-skyactiv

Article is a few years old.

Quote:
The Skyactiv 6-speed automatic uses both a torque converter that locks up at only 5 mph, plus a wet clutch, and a Mechatronic module to communicate between engine and transmission. The engineers met their targets. The torque-converter’s assets are used for smooth launches and intuitive low-speed control; eliminating torque-converter slippage above 5 mph improves efficiency and gives a direct connected feel, much like a manual for response; and designing Mechatronic’s to provide quick, responsive and smooth shifting.
“At Mazda, we wiped the slate clean, and started out with a conventional automatic with planetary gears, then set out to eliminate the blemishes, which are torque-converter slippage, indirect feel, slow shifting, and rough downshifts. We use both a clutch and torque-converter, which locks at 5 mph, because you must have some controlled slippage at low RPMs, but slippage is bad at higher speed.”

 

[michaelluscher]

Hopefully this design puts right all that is wrong with the first gen of DCT's like the DPS6.

CVT's are too slippery and disconnected
Normal Autos are on the way out because modernity
7-9 speed auto boxes are all over the place
Non T/C dry or wet clutch DCT's slip and burn up the clutch in slow speed city driving while being jerkey and unrefined

A DCT w/ TC seems to be the best of the lot

 

[HerrStig]

I always believe everything the ads claim.

 

[Leo99]

How fast is "high speed"?

 

[wemay]

Originally Posted By: michaelluscher

A DCT w/ TC seems to be the best of the lot


Acura's implementation being case-in-point.

 

[4wheeldog]

I have owned an Outback for 3 years and 84k miles. The Subaru CVT makes the car feel slower than it is, because there is no torque thump from shifts. It certainly is no hot rod, but it is quicker than the feedback would make you think. Passing is better than you would expect, especially since you do not get that reassuring kick from the downshift at the start of the pass.

It is very smooth, and gets better mileage than the manual, mainly because the gearing range is considerably wider (Higher ultimate ratio).

If I was choosing a car for excitement, it would not be an Outback, and would likely have a manual trannie. (It is only my second non manual vehicle in 47 years of driving). But I have motorcycles to satisfy my need for ridiculous acceleration. And a 6 speed truck for towing. The Subaru is the most relaxing, and eats miles regardless of road conditions......Which is what it was designed to do.

 

[JHZR2]

Give me an old fashioned MT any day. One clutch to replace instead of two, simpler, lighter, etc.

DCT doesnt have enough saving graces in my book; its rare that I need the 0.000001s shift time in real life.

If I want to drive off mindlessly it really doenst matter what is changing the ratios for me.

But it is insulting that these transmissions, which easily add $500-1000+ to the price of the car, cant be avoided in more and more cases.

 

[IndyIan]

Originally Posted By: JHZR2
Give me an old fashioned MT any day. One clutch to replace instead of two, simpler, lighter, etc.

DCT doesnt have enough saving graces in my book; its rare that I need the 0.000001s shift time in real life.

If I want to drive off mindlessly it really doenst matter what is changing the ratios for me.

But it is insulting that these transmissions, which easily add $500-1000+ to the price of the car, cant be avoided in more and more cases.

+1
A DCT sounds like it would be fun on a track toy if it was tuned properly, but just for daily use, a normal manual is fun enough and simple/cheap.

 

[danthaman1980]

I've driven planetary automatics, DSGs, CVTs, an 8-speed ZF, and Mazda's new hybrid (skyactiv) transmission. Of all the autos out there, I like the Mazda skyactiv the best - that's why I bought one.

Sure, I like manuals too - but Mazda built a really really good transmission in the Skyactiv.

It isn't perfect (I actually wish the torque converter slipped a little bit less off the line) - but I think they absolutely nailed the downshifting/deceleration and pretty much everything above 10 mph.

To all you naysayers - go test drive one and then tell me what you think.

 

[buster]

The Skyactive transmissions in the new Mazdas are awesome. No doubt about it.

I drove the CVT WRX and that too was awesome. Not sure why Mazda thinks you can't have a CVT in a performance application.

I currently drive a manual. I like it a lot but I can't knock some of these new AT/CVTs out there.

 

[wemay]

I drove a 2016 Acura ILX recently and think their new DCT w/TC is excellent. None of the typical jerky, clunky low speed characteristics i had with my 2010 Mitsubishi Ralliart's TC-SST twin clutch.

 

[SwampSurvivor]

CVTs have a long way to go. And a decade of defective-from-the-factory Nissan CVTs made it worse. Not only are the Nissan ones awkward, but they are extremely unreliable. The Nissan CVT is going to be the Olds 350 diesel ...

My first two experiences driving them were a Versa that would randomly rev up to 5000RPM while cruising at a constant rate of speed on the flat and a Sentra that refused to let the engine go above 1100RPM when accelerating hard.

I think there's a use case for each one.

Manual - everything but pure city

Traditional TC auto - Everything but high performance ? ... pure city will increase wear

DCT - Everything but pure city and traffic jams ... good with high performance driving applications

Snowmobile - Good at pure city (no clutch packs to wear out shifting) ... bad at reliability.


I did like the snowmobile transmission in the 2012 Sentra I rented. It worked really , really well in the heavy traffic that is Manhattan/Times square at 6PM on a Saturday. But, at 50K miles, it was nearing the end of its life.

Recently drove a Honda CVT. I liked it. Couldn't tell exactly what it was, but programmed soooooooooo much better than Nissan CVTs. Not sure of reliability as they are too new.


Originally Posted By: danthaman1980
I've driven planetary automatics, DSGs, CVTs, an 8-speed ZF, and Mazda's new hybrid (skyactiv) transmission. Of all the autos out there, I like the Mazda skyactiv the best - that's why I bought one.

Sure, I like manuals too - but Mazda built a really really good transmission in the Skyactiv.

It isn't perfect (I actually wish the torque converter slipped a little bit less off the line) - but I think they absolutely nailed the downshifting/deceleration and pretty much everything above 10 mph.

To all you naysayers - go test drive one and then tell me what you think.



They did drive nicely! They seem to be relatively reliable too.

 

[ARCOgraphite]

Why cant I get over 22 AVE MPG in my new 4 banger rogue? I always best the FED highway MPG on the monronie - but not here. It makes a noise like an old ford PS pump failing- this noticed at warm idle to 1500rpm. Is the CVT tranny pump toast? IIRC car has EPS on the column.

As for CVT - I dont think they are efficient due to belt drive pully losses and hyd pump losses. Recall an old 3 speed T350 would be direct power Xfer through with high efficiency/ low loss in top "gear".
Not going to happen with a belt and two pulleys in oil.

 

[SwampSurvivor]

Originally Posted By: ARCOgraphite
Why cant I get over 22 AVE MPG in my new 4 banger rogue? I always best the FED highway MPG on the monronie - but not here. It makes a noise like an old ford PS pump failing- this noticed at warm idle to 1500rpm. Is the CVT tranny pump toast? IIRC car has EPS on the column.

As for CVT - I dont think they are efficient due to belt drive pully losses and hyd pump losses. Recall an old 3 speed T350 would be direct power Xfer through with high efficiency/ low loss in top "gear".
Not going to happen with a belt and two pulleys in oil.


Apples to oranges, here, but my parents can get high 20s (I can get into the low 30s) out of their Focuscape 2.0L AWD model. 22 MPG is bad!

 

[badtlc]

Originally Posted By: michaelluscher
Hopefully this design puts right all that is wrong with the first gen of DCT's like the DPS6.

CVT's are too slippery and disconnected
Normal Autos are on the way out because modernity
7-9 speed auto boxes are all over the place
Non T/C dry or wet clutch DCT's slip and burn up the clutch in slow speed city driving while being jerkey and unrefined

A DCT w/ TC seems to be the best of the lot


It is NOT a DCT. Not even remotely.

 

[Mykl]

Mazda's auto gearboxes are some of the best. Sure, maybe they're talking trash, but they're backing it up with solid hardware.

 

[brandini]

I agree with Mazda.

Since the TC is locked above low speeds it has the effect and feel of the direct gas pedal to the wheels that a manual has. No auto I've ever driven has felt so good. And even better, the programming is pure genius.

If you're tooling along in the new Mazda and stomp the gas (no double pump required) it's going to drop to the lowest possible gear, in a hurry, and up-shifts are crisp as well. And when you release the pedal, it

and i really want emphasis here

STAYS IN THE GEAR IT'S IN!

Because it knows it's playtime. And it only upshifts once it's convinced you're done running for your life.

And it's glorious.

 

[Pesca]

Originally Posted By: ARCOgraphite
Why cant I get over 22 AVE MPG in my new 4 banger rogue? I always best the FED highway MPG on the monronie - but not here. It makes a noise like an old ford PS pump failing- this noticed at warm idle to 1500rpm. Is the CVT tranny pump toast? IIRC car has EPS on the column.

As for CVT - I dont think they are efficient due to belt drive pully losses and hyd pump losses. Recall an old 3 speed T350 would be direct power Xfer through with high efficiency/ low loss in top "gear".
Not going to happen with a belt and two pulleys in oil.


With a CVT, YOU have to change your way of driving.

If you agree with this concept and change, you will get the results. If you drive a Nissan CVT the same way you drive an automatic, you won't get the results.

I always beat the announced fuel economy, and did it too when I got the Rogue, but I had to change my way of driving. But that was my first, and only, automatic car.

I never ever went above 3000 rpm with my Rogue, even when I had to change lane in traffic, always hovering between 1100 and about 2000 rpms.

 

[Stewie]

Wasn't CVT Honda proprietary?





What I hate of it, is that the fluids are "sealed for life"

 

[flacoman]

Kenichiro Saruwatari, chief engineer on the new Mazda3...
There's a cultural disconnect on the language here.
When he refers to high speed , he means spirited driving.
If it was his primary language we would have seen a different phrase.