E90Post
 


European Auto Source
 
BMW 3-Series (E90 E92) Forum > BIMMERPOST Universal Forums > General BMW News and Cars Discussion > 8 speed automatic transmission likely to replace current 6 speed AT across BMW range



Reply
 
Thread Tools Search this Thread
      11-30-2009, 12:03 AM   #23
akhter
Major
 
akhter's Avatar
 
Drives: F10 LCI 520i Sophisto Grey
Join Date: Oct 2007
Location: Hong Kong

Posts: 1,146
iTrader: (0)

Garage List
Quote:
Originally Posted by Driver72 View Post
Regarding CVT's I don't think they are strong enough.
And as stated in the OP, I agree, I think 8 speeds are too much.
When manuals and autos were 4 speeds, having a 5 speed was a revelation. Then when 6 speed autos AND manuals came out, it made sense for better acceleration AND better gas mileage.

Then Mercedes (I think they were first) brought us the 7 speed auto.
Personally, I don't know of too many people who thought, "awesome, 7 speeds, that's going to make a HUGE difference and is welcomed."
Mercedes skipped 6 speeds. And there 7 speed autos DID improve performance and gas mileage in their vehicle line. But would it of improved performance and gas mileage if they would of gone from a 6 speed to a 7 speed? I'm not so convinced.

Lexus wanted to upstage MB by going to the 8 speed auto.
And I don't think I've read a single review of it, where testers were rejoicing over having 8 speeds. Quite the contrary, where they've felt it too much.

So too me, nobody has "rejoiced" adding additional gears since 6 speeds have become common.

It just makes for too many gears.
4 underdriven gears
1 slightly overdriven gear (.90)
1 significantly overdriven gear (like .75) for highway crusing

I personally think that's perfect.

So IF I was to of had a say in the new ZF 8 speed auto, I would of made ALL the advancements they made with it, and all the robustness of it, and made it a new 7 speed auto AT MOST, and possibly just made it a better 6 speed auto. And in doing so, they probably could of made it 20-30 lbs lighter (since they made the new 8 speed the same weight of the current 6 speed).
Your deductions (they can make a 6 speed with the same efficiencies with fewer gears for less weight/complexity) don't seem based on any real data or science.

If I recall reading an article about the gearbox, the spokes person from ZF said that when creating this unit, their goals were:
1) More fuel efficiency
2) More power efficiency

and the number of gears were not an important data point other than whats needed for the above 2 points.

I agree 8 sounds too much and is annoying when doing manual shifting using paddles, but when i was driving my 335i AT, the 1st gear was almost never used unless I was at a red light trying to beat someone. otherwise, i would use the paddles to shift up or down never caring which actual gear i was at so 6 or 8 probably won't make much difference. face it, auto gear boxes are the not going to be what you think in a few years and we may end up with 10 gears or something like CVT to completey do away with gears.

I recall reading somewhere this box has 5 clutches which if true means that DCT boxes will seem like a interesting experiment of the past in a few years while everyone jumps on similar tech.
akhter is offline  
0
Reply With Quote
      11-30-2009, 12:08 AM   #24
akhter
Major
 
akhter's Avatar
 
Drives: F10 LCI 520i Sophisto Grey
Join Date: Oct 2007
Location: Hong Kong

Posts: 1,146
iTrader: (0)

Garage List
Quote:
Originally Posted by Stankia View Post
I bet it's gonna cost a lot to fix.
like the current DCT/6 speed boxes, no one will be repairing these as the cost will probably be higher than to replace.
akhter is offline  
0
Reply With Quote
      11-30-2009, 03:35 AM   #25
bimmerfrei
Enlisted Member
 
Drives: 2011 528i
Join Date: Nov 2009
Location: Sweden

Posts: 44
iTrader: (0)

From a European perspective, the 8 speed auto seems great. We drive through Germany a lot, and even though my 335d doesn't rev a lot, two extra gears would be great when you travel at speeds above 150-160 km/h. Great improvement in my opinion.

/Christian
bimmerfrei is offline   Sweden
0
Reply With Quote
      11-30-2009, 04:39 AM   #26
StewartM
Enlisted Member
 
StewartM's Avatar
 
Drives: Ford Fiesta Mk7 1.25 Zetec
Join Date: Jul 2005
Location: Scotland

Posts: 40
iTrader: (0)

So far, magazine road tests of the 5 Series GT and 760 Li have been very complimentary about the new 8 - speed 'box. Always in the right gear, almost imperceptible shifts.

Yes, the Merc 7 - speed and Lexus 8 - speed have come in for criticism, especially for being unsure what gear they want to be in. The new ZF is nothing like them ! !

The ZF 6 - speed was widely regarded as the best automatic you could get. The new 8 - speed moves the game on. It's not just the 6 - speed with an extra gear top and bottom, but quite different internally, improving its efficiency.

The fact that the new 520d will have this 'box makes an even bigger mockery of MB's decision to give the 4 cylinder E-Class the 5 -speeder.

Stewart.
StewartM is offline  
0
Reply With Quote
      11-30-2009, 05:46 AM   #27
marcel b
Lieutenant Colonel
 
marcel b's Avatar
 
Drives: 1M Coupe
Join Date: Jun 2009
Location: Europe

Posts: 1,864
iTrader: (0)

I think 8 speed are great! I've the 7 gear DCT and I really value the additional gear. low revs when cruising, amazing fuel economy. especially with low rev high torque engines like the 335i, it works flawless. it can easy pull in 7th with 1400 rpm. when pushing the shorter gears are good, and with the seamless shifting no time is lost when shifting. I agree that with a manual box it would make less sense. Let's see.
marcel b is offline  
0
Reply With Quote
      11-30-2009, 08:59 AM   #28
sokdo
Lieutenant
 
sokdo's Avatar
 
Drives: 335i E92
Join Date: Jul 2009
Location: Fullerton, CA

Posts: 582
iTrader: (0)

When does it end? 9? 10?
sokdo is offline  
0
Reply With Quote
      11-30-2009, 06:00 PM   #29
vladberca
Brigadier General
 
vladberca's Avatar
 
Drives: '09 jetta tsi 6mt
Join Date: Oct 2009
Location: Craiova

Posts: 3,572
iTrader: (0)

I don t think they will add more than 8 gears... it s great for fuel efficiency when u drive with more than 200km/h on motorway...
vladberca is offline   Romania
0
Reply With Quote
      11-30-2009, 10:45 PM   #30
brinx38
Private
 
brinx38's Avatar
 
Drives: SG E92 335i w/iDrive
Join Date: Sep 2009
Location: N.Y.

Posts: 80
iTrader: (1)

Garage List
2007 335i  [0.00]
Send a message via Skype™ to brinx38
There is also a nice vid about the 8spd on the ZF website.

Check it out at

http://www.zf.com/corporate/en/produ...nsmission.html

...
brinx38 is offline   United_States
0
Reply With Quote
      11-30-2009, 10:54 PM   #31
domobrown
Banned
 
Drives: Audi RS5 S-Tronic
Join Date: May 2009
Location: Salzburg, Austria

Posts: 512
iTrader: (0)

How does the tranny sport both a torque converter and a clutch pack? What's the advantage?
domobrown is offline   Austria
0
Reply With Quote
      11-30-2009, 11:56 PM   #32
amgthis
Tire Racks
 
amgthis's Avatar
 
Drives: AW 1M Coupè
Join Date: Apr 2008
Location: San Francisco, CA

Posts: 1,228
iTrader: (0)

Quote:
Originally Posted by domobrown View Post
How does the tranny sport both a torque converter and a clutch pack? What's the advantage?
Well, I'm guessing faster shift times for a start. And the car can still creep forward with the torque converter.
amgthis is offline   United_States
0
Reply With Quote
      12-01-2009, 01:40 AM   #33
Garduna
Brigadier General
 
Garduna's Avatar
 
Drives: 128i Sedona Red
Join Date: Oct 2008
Location: Toronto

Posts: 4,009
iTrader: (3)

I like my 6 speed thank you very much!
Garduna is offline   Canada
0
Reply With Quote
      12-01-2009, 03:15 AM   #34
footie
Major General
 
footie's Avatar
 
Drives: ????????????
Join Date: Oct 2007
Location: BMW M3 will get a V6TT

Posts: 7,507
iTrader: (0)

Garage List
2008 E92 M3  [0.00]
It says in the info that it takes 200ms to execute a shift but I was sure we were told it was quicker than that. My memory must be acting up in my old age.

In any case it didn't feel much different to that of the DCT though clearly it was.
footie is offline   No_Country
0
Reply With Quote
      12-01-2009, 01:06 PM   #35
mtechnik3
Colonel
 
mtechnik3's Avatar
 
Drives: F30 335i M Sport
Join Date: Aug 2007
Location: Rochester Hills, MI

Posts: 2,350
iTrader: (21)

Start stop feature coming to automatics

Wouldn't this get pretty annoying if you have an aftermarket exhaust? My car constantly shutting off and then back on during rush hour might get irritating...

I understand this will be implemented to reduce emissions, and is a part of BMW big efficient dynamics plan.

http://www.bimmerfile.com/2009/11/30...to-automatics/

We have heard from reliable sources that BMW along with ZF have been developing the newest 8 speed transmission to also work with Stop/Start. Stop/Start is a technology developed to allow the engine to turn off automatically when the car is stopped for a period of time (at a traffic light) and the engine will turn back on when the accelerator is depressed.

Currently, this technology has been reserved for 4 cylinder engines coupled with a manual transmission in markets outside the US. This new offering would allow the use of Stop/Start in vehicles with larger displacements and of course in different markets that prefer the automatic.

Earlier in the year we learned that BMW will be transitioning its current lineup of 6 speed autos to 8 speeds by model year 2013. The 8 speed debuted in the 760Li and will be featured in the 5 GT as well as the 5 series this spring. There has been no set date as to when this new feature will make it’s debut but one can expect it first in the 7 Series hybrid this spring and other models after.
__________________

2013 F30 335i ///M-Sport | Alpine White
mtechnik3 is offline   United_States
0
Reply With Quote
      12-02-2009, 05:13 PM   #36
mapezzul
Special Agent
 
mapezzul's Avatar
 
Drives: Depends on the day!
Join Date: Jul 2005
Location: Bavaria

Posts: 1,736
iTrader: (1)

Quote:
Originally Posted by mtechnik3 View Post
Wouldn't this get pretty annoying if you have an aftermarket exhaust? My car constantly shutting off and then back on during rush hour might get irritating...

I understand this will be implemented to reduce emissions, and is a part of BMW big efficient dynamics plan.

http://www.bimmerfile.com/2009/11/30...to-automatics/

We have heard from reliable sources that BMW along with ZF have been developing the newest 8 speed transmission to also work with Stop/Start. Stop/Start is a technology developed to allow the engine to turn off automatically when the car is stopped for a period of time (at a traffic light) and the engine will turn back on when the accelerator is depressed.

Currently, this technology has been reserved for 4 cylinder engines coupled with a manual transmission in markets outside the US. This new offering would allow the use of Stop/Start in vehicles with larger displacements and of course in different markets that prefer the automatic.

Earlier in the year we learned that BMW will be transitioning its current lineup of 6 speed autos to 8 speeds by model year 2013. The 8 speed debuted in the 760Li and will be featured in the 5 GT as well as the 5 series this spring. There has been no set date as to when this new feature will make it’s debut but one can expect it first in the 7 Series hybrid this spring and other models after.
You can turn the feature off via a button- having experienced stop/go in the EU I can say it is a little unnerving at first then becomes second nature- As for the exhaust depends on the type.

Not sure if I had mentioned it before but after driving the 8 speed in a variety of situations I can say that it is fine transmission and can't wait to try it in the TU form (faster shifts like the 335 version thanks to the upgraded torque converter etc.).
mapezzul is offline   United_States
0
Reply With Quote
      12-03-2009, 02:56 PM   #37
burberry
Too Poor To Drive
 
Drives: E93 M3
Join Date: Nov 2009
Location: Brooklyn, NY

Posts: 1,975
iTrader: (3)

wow 8sp sounds fckin awesome
__________________
burberry is offline   United_States
0
Reply With Quote
      12-03-2009, 03:27 PM   #38
mapezzul
Special Agent
 
mapezzul's Avatar
 
Drives: Depends on the day!
Join Date: Jul 2005
Location: Bavaria

Posts: 1,736
iTrader: (1)

Quote:
Originally Posted by burberry View Post
wow 8sp sounds fckin awesome
8 speed will be the end all (not 10 speed etc.), BMW and ZF had created all sorts of algorithms and computer simulations that basically state that anything greater than 8 is pointless (unless there are infinite ratios...)

The ability it has to skip gears and not hunt and peck for the optimal gear on the upshift is leaps and bounds above other brands itinerations.
mapezzul is offline   United_States
0
Reply With Quote
Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 09:02 PM.




e90post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST