mmarshall

The traditional complaints with CVTs (besides some questionable durability on the early ones) are, of course, motorboating and rubber-banding (I'm sure you know what those two terms mean, so I won't explain them). But the latest CVTs, especially those from Nissan and Subaru (as I understand it, they come from the same supplier) have done an excellent job of dealing with those two problems. ....and they now have paddle-shifters with programmed "gears" in the drive-belt that simulate the effect of a regular stepped-automatic.

JessePS

You would be like a truck driver.

RocketGuy3

iTrader: (1)

It seems pointless. Once you want that many gears, why not just throw in a CVT and call it a day?


Err... I have a six-speed auto, and I'm in 6th by 60.

But I suppose you're probably talking about full throttle driving.


Heh, true, but there were two overdrive ratios in 6-speeds years ago.


Personally, I'm not familiar with those terms. Mind explaining? Going by the name alone, they sound like they would mainly be problems with those pulley-based CVTs.

mordecai

But if Lexus does it, it'll be amazing right? Well, probably. I was expecting a 10-speed automatic in the next generation LS.

Justin2JZ

Yes I was talking about WOT.

Hoovey689

iTrader: (16)

already talk of 10 speeds?! Let's let Mercedes debut their 9-speed auto first THEN we'll talk 10 hah

GSteg

iTrader: (15)

10 speed is too much. Hell I think anything over a 6spd is nonsense since you're reaching the point of diminishing returns.

bad co

Obviously these engineers see a benefit to it, you all know that manufacturers are frugal it was only last year that gm started ditching the old 4spd and honda came out with a 6spd. I HATE Cvt I can't stand that when I'm at WOT the car is humming at 4k

LexFather

Usually the new auto with more gears is lighter and more efficient. There is no denying for most people around town or on the highway there is a benefit for more gears as it helps MPG as it keeps RPM lower. This could be a great marketing ploy for them and it will help with efficiency. It sounds silly maybe but so do 18 way power seats, 8 driver select modes, etc etc

Blackraven

Point taken

However, for the manufacturer, you'd have to make sure that you won't reach the point of diminishing returns. There is a saying in life wherein: "You should not eat more than what you can chew". There will definitely come a point wherein "more is always better" does not always apply...............especially once you reach the point of diminishing returns.

Perhaps, to draw the line, perhaps a question would help:

@1SICKLEX

You seem fine with a ten speed auto gearbox. HOWEVER, what do you think of 14-speed autos? Or even 20 speed autos? Isn't that overkill already? (i.e. we are going the way of SHIMANO here for our automobiles)

Would you still consider those something that is needed in the automotive industry? Yes or no?

P.S.
I can't see why some people hate CVTs.

Remember, if you want this numbers game with gears and speeds, then CVTs are the answer. Infinite possibilities...........yet some people hate them.

@spwolf

I remember that there are some Europeans who do not like CVTs (i.e. Jeremy Clarkson is a staunch critic who dislikes CVTs with a burning passion).

Question is why?

T0ked

iTrader: (2)

If the 10 speed is done correctly, what's the problem? I'm a little surprised by all the nay-sayers to this thread. Now a gated 10 speed is a bit ridiculous, but with all the paddle shifters in most cars already and good programming, a 10 speed auto should be brilliant. With smaller, more fuel efficient engines most likely making their way down the food chain, more efficient transmissions will become key. More gears, more likely to stay in the engines sweet spot in terms of power and efficiency. If Hyundai wants to be known as the first auto maker with a 10 speed transmission, they better get the programming dead on or else it will be known as what-should-never-have-been. I'll give Hyundai the benefit if the doubt here. I know their newer models haven't been perfect, but I have not heard of poor transmission programming to be one of them. But this is the route we are headed for the sake of keeping a good balance between fuel efficiency and performance.

Now, I don't know the development costs between CVTs and more mechanical cogs, but CVTs have come a long way and yet they still have a ways to go. Nissan has had teething problems with their CVTs and the Altima with it has been a dog. From my personal experience, it was either jerky with sudden "down shifts" or just no response to the pedal at all. I hated driving my gf's Altima. Aside from bragging rights, are there advantages to developing a more complicated traditional gear box vs a CVT?

I8ABMR

seems like total overkill but I will admit the added gears in my LS are great for fuel economy and acceleration. I maxed my car yesterday and it was crazy to see the needle drop from redline to like 5500 rpm. The car just keeps pulling with those really close gears. I wonder what a 10 speed would feel like.

spwolf

because they feel weird... and they really do. Thats why they all have manual modes these days.

mmarshall

Motorboating occurs when the throttle is applied to a CVT powertrain and the engine RPM spikes up for a second or two, with little or no aceleration. it is similiar to what happens on a outboard-motorboat with a fixed-pitch propeller....the engine spins awhile, and the prop slips through the water, before bite is noticed and the boat starts taking off. CVT belts, if working properly, of course don't slip, but the effect sometimes feels the same.

Rubber-banding occurs when the powertrain, under throttle, surges up and down on acceleration, similiar to what would happen if you had a large rubber-band driving the CVT while expanding-and-contracting. It is also somewhat similiar to the old days before fuel-injection, with emission-choked carburators, when cars ran with too-lean fuel mixtures, and alternately surged/hesitated on acceleration.

spwolf

p.s. Passat 3.6l 6 speed AT has 3 overdrive ratios :-).