GM and Ford to Co-develop 9 & 10 Speed Autos

music · September 29, 2012

Sorry if this is a repost:

GM, Ford jointly developing 9- and 10-speed transmissions: http://www.autonews....5#ixzz27rXIxNa6

Doug_Scott · September 29, 2012

Don't understand why they don't just develop a more robust CVT. It would be a far simpler device when compared to 6, 7, 8, 9 or 10 speed transmissions.

MikeNH · September 29, 2012

Durability. Plus I hate them.

becker87 · September 29, 2012

I would love to see what kind of milage they could pull from a 4.5L Duramax and a 10 speed. I'm guessing 30+ MPG would be no problem. Sign me up!!

HEMICAT · September 29, 2012

I would love to see a 10 speed behind a small DI V8 with a turbo like Ford's ecoboost. A CVT in a truck would be disgusting- no disrespect.

music · September 29, 2012

Don't understand why they don't just develop a more robust CVT. It would be a far simpler device when compared to 6, 7, 8, 9 or 10 speed transmissions.

CVT designs aren't as efficient as gear-to-gear. The motivation for more gears is higher efficiency. I won't be surprised if the torque converter is completely gone on the 10 speeds. Does Dodge have a TC on their 8-spd?

Doug_Scott · September 30, 2012

Don't understand why they don't just develop a more robust CVT. It would be a far simpler device when compared to 6, 7, 8, 9 or 10 speed transmissions.

CVT designs aren't as efficient as gear-to-gear. The motivation for more gears is higher efficiency. I won't be surprised if the torque converter is completely gone on the 10 speeds. Does Dodge have a TC on their 8-spd?

What will they use to allow the engine to keep running at stop lights while in gear?

kstruckcountry · September 30, 2012

Yeah, I don't understand either. You have to have something to get you moving, even if gear to gear is perfect.

tanked_darren · September 30, 2012

Don't understand why they don't just develop a more robust CVT. It would be a far simpler device when compared to 6, 7, 8, 9 or 10 speed transmissions.

CVT designs aren't as efficient as gear-to-gear. The motivation for more gears is higher efficiency. I won't be surprised if the torque converter is completely gone on the 10 speeds. Does Dodge have a TC on their 8-spd?

Explain how the engine stays at idle while stopped at a light without the torque converter. Shifts into neutral just before the engine dies when your stopping?

ujtruck · September 30, 2012

Yeah, I don't understand either. You have to have something to get you moving, even if gear to gear is perfect.

electromagnetic clutch can do it

music · September 30, 2012

I'm really not sure what they would try to use in place of a TC, but I'd imagine them using an automated clutch of some type. A torque converter is more than just a clutch, of course. It creates hydraulic torque amplification, but it's less efficient than using a clutch w/ a steeper 1st gear. I have no insider info on this, just guessing based on where they may find improvement. It may be that a small TC will still be used (?).

I noticed on the 2013 RAM 1500 ads w/ the 8-spds that they are cutting the motor off at a stop, and starting it when the brake is released. I *think* the 8-spds still use a TC, but I'm not sure about it.

music · September 30, 2012

Well... a quick search found this: http://www.allpar.co...ssions/ZF8.html. They show a TC on this ZF 8-spd auto, but mention that it locks a lot faster than previous generations, for higher efficiency (which makes sense).

Wires · September 30, 2012

Well... a quick search found this: http://www.allpar.co...ssions/ZF8.html. They show a TC on this ZF 8-spd auto, but mention that it locks a lot faster than previous generations, for higher efficiency (which makes sense).

That's how the 6speed in my 335 is. TC locks up at a super low RPM (around 1500). In 1st gear, it'll chug under light throttle like a manual does (if you didn't know better, you'd think it was a manual).

One of the issues with the CVT is the engine is stuck at peak HP RPM during acceleration, so the engine seems to race. I wonder what sort fo HP/TQ that steel belt is good for?

Sort of wonder WTF point of 10 gears is. I'm sure it saves some MPG, but it's getting to the point when something like that blows, you won't be able to afford to repair it. Might as well get that high/low sub transmission in there.

slimjim2525 · September 30, 2012

Why is my only question.

Doug_Scott · September 30, 2012

Well... a quick search found this: http://www.allpar.co...ssions/ZF8.html. They show a TC on this ZF 8-spd auto, but mention that it locks a lot faster than previous generations, for higher efficiency (which makes sense).

One of the issues with the CVT is the engine is stuck at peak HP RPM during acceleration, so the engine seems to race. I wonder what sort fo HP/TQ that steel belt is good for?

CVT use the peak torque rpm, and even then it is not always even than that. Under full throttle they will use peak torque rpm, light throttle they don't. HP is merely a mathematical number based on torque and rpm. They really need to educate consumers and drop the HP in ads. HP numbers are meaningless in real world driving.