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2011 Audi A8 To Get 8-Speed Automatic

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Old Aug 28, 2009 | 07:12 AM
  #16  
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Originally Posted by mmarshall
Of course the 8-speed is more flexible, but quite complex and difficult to produce. If you're going to have that kind of flexibility, why not just use a simple CVT...or develop a CVT that will take V8 torque?
i'm sure someone's trying, but maybe because it's not easy to make it cost effective or trouble-free, with belts that won't snap or get stretched.
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Old Aug 28, 2009 | 07:14 AM
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How about the CVT in the GS hybrid, I think that use a planetary gear CVT.
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Old Aug 28, 2009 | 07:20 AM
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Originally Posted by mmarshall
Well, is that any different from Lexus copying the BMW Bangle-Butt trunk lid on the LS460?
Completely wrong, they look nothing alike.
The S-class trunk-lid did copied the 7-series trunk-lid however ...
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Old Aug 28, 2009 | 07:34 AM
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Originally Posted by MPLexus301
If I recall, the 8AT actually uses less parts than the older 6AT and weighs less.

As for CVTs, personally I do not like them. I know it is probably fine for some people but hearing a constant groan under moderate or heavy acceleration gets old IMO. I like the feeling and hearing the revs build, upshift, revs build, upshift, etc.

I wouldn't mind one if I owned a Prius or something, but not in any car that I would put my foot into every now and then.
I dunno, I don't think a CVT sounds so bad.

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Old Aug 28, 2009 | 07:41 AM
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I dont know, it still sounds strange to me not hearing that shift note from the power train. Maybe I can do what that guy in the old commerical did, make my own shift sound when driving a CVT
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Old Aug 28, 2009 | 07:48 AM
  #21  
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Originally Posted by Gojirra99
The S-class trunk-lid did copied the 7-series trunk-lid however ...

Most people seem to forget that the current S class rear design was already showcased long before the Bangle 7 series was revealed to the public.

The 1996 Maybach concept


Images of the rear are difficult to find but the production version doesn't look much different.
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Old Aug 28, 2009 | 09:01 AM
  #22  
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Originally Posted by Gojirra99
Completely wrong, they look nothing alike.
The S-class trunk-lid did copied the 7-series trunk-lid however ...
I have to disagree. No, it is not a perfect match, but the similiarities.....and the timing........are unmistakable. I am also not the only one on CL to notice it......there has been a lot of discussion about it.

Of course, styling is objective, and is not necessarily a matter of "right" or "wrong" when personal preferences are concerned. Even the Pontiac Aztek, for example, found some buyers.
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Old Aug 28, 2009 | 10:49 AM
  #23  
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Originally Posted by mmarshall
CVTs, if done correctly, can actually increase both acceleration AND gas mileage.....their efficiency is outstanding. Check out the new Subaru 2.5 Legacy/Outback or Nissan V6 CVTs and you will see what I mean. Older CVTs sometimes had weird sensations, but most of those have been engineered out of the new Subaru/Nissan units....and they have 6 programmable gear "ranges"
Agreed.

More development and advancements in CVT usage and technology would definitely improve its potential (even to the point that staunch CVT critic Jeremy Clarkson may start accepting them)....
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Old Aug 28, 2009 | 10:58 AM
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Originally Posted by mmarshall
I don't play favorites. I think that both the Mercedes 7-speeds and Lexus 8-speeds are overkill, and I'll probably feel the same about Audi's new 8-speed. In most cases, you usually don't need more than 5 or 6....especially for most daily driving. If you're going to have more than that, you might as well use a CVT, with a infinite number of ratios.
I disagree as do the leaders and skilled engineers of these premium car companies. The Lexus and Mercedes transmissions are excellent.

I do agree with the potential for CVT in many applications, now that the performance and reliability continues to improve.

The A8 obviously needs some major rework, with sales just over 100 units a month, it's lagging the competition badly.
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Old Aug 28, 2009 | 11:01 AM
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Originally Posted by The G Man
I dont know, it still sounds strange to me not hearing that shift note from the power train. Maybe I can do what that guy in the old commerical did, make my own shift sound when driving a CVT
The artifical steps/speeds in many of the newer CVTs reduces that motorboating sensation that you mentioned above. Long term reliability still needs to be proven.
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Old Aug 28, 2009 | 05:16 PM
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I wouldnt want a CVT for that reason. I want to se how well it does after 200k miles. Plus they cost you torque a lot of the times. I want torque.

As far as the 8 speed I thought that the industry would have learned its lesson after the set up in the ISF. Its pretty well accepted in the automotive journalistic community that 8 speeds is a little over done. The car is always changing gears and you really only use 6. Look it up. Even on Top Gear they trashed the 8 speed because of the massive jumping n the gears all of the time
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Old Aug 28, 2009 | 06:09 PM
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Originally Posted by RXSF
yes i remember lexus saying that the 8 speeder was lighter than the 6 it replaced. plus many people hate driving CVTs. in all fairness, the merc 7 speed is the best auto gearbox I have ever driven. it is much faster at reacting that lexus autos.

plus cvts dont scream luxury car, which is why that are widely used in nissans etc etc, and just hybrids because of their fuel efficiency
Not sure what MB 7 speed you're referring to....but there's not a snowball's chance in hell that our Merc's 7 speed is even close to as fast or as smooth as the 8 speed in my F.
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Old Aug 28, 2009 | 06:19 PM
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Originally Posted by I8ABMR
I wouldnt want a CVT for that reason. I want to se how well it does after 200k miles. Plus they cost you torque a lot of the times. I want torque.
CVTs are actually more efficient at transmitting torque than conventional geared automatics because their infinite gear ratios can keep the engine in its peak power bands more of the time. The problem is that CVT belt-chains haven't reached the durablity point, yet, where they can stay reliable in really high-torque engines.

As far as the 8 speed I thought that the industry would have learned its lesson after the set up in the ISF. Its pretty well accepted in the automotive journalistic community that 8 speeds is a little over done. The car is always changing gears and you really only use 6. Look it up. Even on Top Gear they trashed the 8 speed because of the massive jumping n the gears all of the time

Agreed. 7 and 8-speed trannies mean a lot of shifting as the speed and RPM loads vary. And more shifting, of course, means more wear on the transmission's clutch assemblies, valve bodies, and the gears themselves, shortening transmission life.
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Old Aug 28, 2009 | 06:29 PM
  #29  
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Originally Posted by CDNROCKIES
Not sure what MB 7 speed you're referring to....but there's not a snowball's chance in hell that our Merc's 7 speed is even close to as fast or as smooth as the 8 speed in my F.
lol, well lets not bring the ISF into this, which shifts faster than most cars on the road. I will give you that the merc gearbox is not as smooth, but when it comes to predicting which gear I want, it is quite good at that.
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Old Aug 30, 2009 | 03:04 AM
  #30  
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I still think most will agree that 8 speeds is a little over done. I am wondering how well the 7 sped in the new Infinitis is working
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