http://www.msnbc.msn.com/id/4778754/



Sounds pretty cool to me, enjoy!

 

Not really big news - ZF has had a 6 speed auto in production for several years, it's used in some Jags, BMWs, and a few others - Mercedes has a 7 speed auto in production right now.

As for this quote from the article:He's very wrong. The future of transmissions is CVTs and Borg-Warner DSG like in the Audi 3.2TT. The conventional slushbox automatic (of which the 7 speed might be the future insofar as slushboxes are concerned, not the 6 speed) is less efficient, less smooth, heavier than either a CVT or DSG.

Regards,
Gordon

 

I disargee biggest thing since the moon landing! :D j/k

I just thought it was noteworthy. I like to see the US car makers trying to improve.

 

CVT are out
IVTs are in

Double clutches are the 'in' transmission for the next 5 years.

 

I think the big news in this tranny is that is (I think) the first one designed for FWD applications.

 

The VW beetle cabrio has had a transverse 6 speed automatic for the last ~8 months.

 

Yes but this is the first domestic transverse 6-speed slush box!

 

CVT's can have infinite gear ratios within an upper and lower limit and are lighter than 4 speed autos. Yet auto makers program them to simulate a tranny with discrete gears/changes. At the same time the auto makers keep adding gears to normal auto tranny's (7 for MBZ) so they can perform more like a tranny with infinite gear ratios. Ironic.

 

The real issue with CVTs is the chain and variators.
They have durability issue with transfering full power and changing ratios, that wears out the chain/variators.
The Audi multitronic has 6:1 ratio coverage, and the Nissan Xtroid has 5.4:1 but the Nissan can handle a little more torque than the Audi.

The 6 speed automatic in the Lexus LS430 has 6.5:1 coverage, MB 7g-tronic has roughly 6:1 and so does the ZF 6HP19,26,32 and the Aisin Warner in the Touareg, Cayenne

The ZF 7P-has 7.28:1 because ZF removed the torque converter.
The GM/Ford X22F can handle 400Nm and has roughly 6:1 coverage.

 

He's very wrong. The future of transmissions is CVTs and Borg-Warner DSG like in the Audi 3.2TT. The conventional slushbox automatic (of which the 7 speed might be the future insofar as slushboxes are concerned, not the 6 speed) is less efficient, less smooth, heavier than either a CVT or DSG.

I think that's a bit strongly worded. 6-speed automatic transmissions are definitely going to dominate at least the immediate future of automatic transmissions. 10 years ago, most vehicles had 4-speed autos, now the majority have either 4- or 5-speeds, and many new vehicle models are coming out with 6-speeds (very few 7-speeds out there, and not many in the works, either). CVTs are becoming more and more common and I would agree that they will play an important role in the future of ATs, however it's a bit early to say what the role will be.

I think the next few years will tell us a lot about where the future of the automatic transmission is headed. With CVTs being offered in Ford's new flagship sedan, the Five Hundred, and the Freestyle crossover, this will be the first time we've seen a CVT in vehicle programs with such large markets. It could backfire if people don't receive the CVT well or reliability isn't what customers expect. The fact that CVTs are currently being calibrated to simulate fixed-ratio transmissions says something about how well they're being received. Acceleration capability and fuel economy are being sacrificed to give customers what they would normally expect of a powertrain... it might take a while before people can get accustomed to the sound of an engine that maintains a nearly constant speed while accelerating.

Another issue with CVTs: torque capacity. I think it will be quite some time before we see this technology on large SUVs and pickups, which dominate the North American market. These are the reasons why, at least for the next decade or so, conventional 6-speed autos will be king of the automatic transmission.

 

It said only for front wheel drive cars right? Or can they use it in rear wheel drive too?

 

http://media.gm.com:8221/division/20...6speed_fwd.pdf

 

If they did a "mid engined" rear wheel driver, ala Toyota MR2, the tranny could be used. Otherwise it is only good for front drive.