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-   -   9 speed auto transmission ? (http://forums.pelicanparts.com/off-topic-discussions/831718-9-speed-auto-transmission.html)

rfuerst911sc 09-28-2014 09:39 AM

9 speed auto transmission ?
 
Just saw a commercial for a Chrysler 200 that has a 9 speed auto transmission ? Wow I remember when 5 speed auto's were the rage ! How time flies. So how complex are these when you get that many gears ? I assume more clutch packs/servos to go wrong ?

kaisen 09-28-2014 09:46 AM

Often they are less complex as they are engaging the same ratios in two or three combos to make one 'gear'. Ford and GM have co-developed ten speed transmissions that will be out next year. At some point there is a diminishing return, but a wider spread (lower first, taller top gear) really helps both performance and fuel economy.

Nickshu 09-28-2014 10:52 AM

Why not just build a CVT? 8,9,10 speeds seems silly to me.... As in from a stop light the vehicle will shift thru 7 gears before I hit the other side of the intersection. Seems like that would get really annoying?

gshase 09-28-2014 11:00 AM

The only problem I can see is it is made by Chrysler.

kaisen 09-28-2014 11:28 AM

Quote:

Originally Posted by gshase (Post 8282054)
The only problem I can see is it is made by Chrysler.

Chrysler's 9 speed automatic is manufactured by ZF.... same as BMW and Porsche

5String43 09-28-2014 11:33 AM

What Nick said. What, exactly, is the practical difference between something like this and a CVT?

kaisen 09-28-2014 11:38 AM

Quote:

Originally Posted by 5String43 (Post 8282080)
What Nick said. What, exactly, is the practical difference between something like this and a CVT?

Pump losses in a CVT are giant. Typically quite fuel efficient at low speeds, and much less efficient at freeway speeds. Also, CVTs aren't anywhere near as strong, so they're not good for towing or high performance applications.

kaisen 09-28-2014 11:43 AM

Quote:

Originally Posted by Nickshu (Post 8282044)
Why not just build a CVT? 8,9,10 speeds seems silly to me.... As in from a stop light the vehicle will shift thru 7 gears before I hit the other side of the intersection. Seems like that would get really annoying?

Many applications will choose shift algorithms to skip gears when possible. They may start in second and shift right to fourth under part throttle normal driving.

dw1 09-28-2014 12:15 PM

I was in a Chevy showroom recently and did a double-take when I saw the 7-speed manual in the new Corvette Sting Ray.

A car with this much torque, and it needs a 7-speed? I know it is probably a way for the car to meet fuel economy standards, but still...

island911 09-28-2014 01:33 PM

Quote:

Originally Posted by kaisen (Post 8282085)
Pump losses in a CVT are giant. Typically quite fuel efficient at low speeds, and much less efficient at freeway speeds. Also, CVTs aren't anywhere near as strong, so they're not good for towing or high performance applications.

Exactly.

TheRedSlantnose 09-28-2014 03:04 PM

As many people already know, the design is in pursuit of fuel economy, but instead of saving a dime by simply using shorter gear ratios, they go ahead and build a transmission with more gears. I don't really get it either.

If transmissions continue to evolve this way, soon we'll have cars that have more gears than a semi truck :p

onewhippedpuppy 09-28-2014 03:24 PM

Quote:

I was in a Chevy showroom recently and did a double-take when I saw the 7-speed <u>manual </u>in the new Corvette Sting Ray.<br>
<br>
A car with this much torque, and it needs a 7-speed? I know it is probably a way for the car to meet fuel economy standards, but still...
I believe the new C7 will get approximately 30 MPG on the highway, so it's not a gimmic.

LakeCleElum 09-28-2014 04:20 PM

Quote:

Originally Posted by kaisen (Post 8282093)
Many applications will choose shift algorithms to skip gears when possible. They may start in second and shift right to fourth under part throttle normal driving.

Yep, in the interest of fuel ratings, always in too high of a gear. Many have no way for a driver to override the gear selection to punch it and wind it out.........

Por_sha911 09-28-2014 05:31 PM

The big three:
Form follows marketing

Peterfrans 09-28-2014 08:35 PM

My bmw 3-series daily driver has a 8 speed auto. It is really very very good.

VincentVega 09-28-2014 08:40 PM

Nothing wrong with it but I sure with the 4 speed in my truck was a 5 or 6 speed. Towing or hauling a load it hunts on hills more than I like, an extra gear or 2 would be nice.

Quote:

Many applications will choose shift algorithms to skip gears when possible. They may start in second and shift right to fourth under part throttle normal driving.
In my limited experience in recent trucks this has been the case. Smooth shifts and its seemed to work great, always seemed to a gear for the load/speed.

onewhippedpuppy 09-29-2014 03:23 AM

Quote:

Originally Posted by LakeCleElum (Post 8282361)
Yep, in the interest of fuel ratings, always in too high of a gear. Many have no way for a driver to override the gear selection to punch it and wind it out.........

That's my only complaint, many modern automatics are designed to lug the car in the highest gear possible to maximize MPG and are hesitant to downshift. Those that have a sport mode are typically better. On my 2012 F150 I have a 5Star performance tune that makes the automatic hold gears longer and downshift quicker, particularly when in tow/haul mode. It makes the truck much more pleasant to drive, and it spends less time hunting when I tow.

DaveE 09-29-2014 05:44 AM

Our 2012 A4 has an 8 speed auto, but it has a sport mode. I'm amazed at how what must be a pretty heavy car (I think 3600 pounds) can accelerate with a 2.0 turbo.


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