[akhter]

Originally Posted by Driver72

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]

Originally Posted by Stankia

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.

[bimmerfrei]

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

[StewartM]

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.

[marcel b]

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.

Can't wait for the 8speed. The wife is going to wait and get it with the new 3 series then

[sokdo]

When does it end? 9? 10?

[vladberca]

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...

[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

...

[domobrown]

How does the tranny sport both a torque converter and a clutch pack? What's the advantage?

[amgthis]

Originally Posted by domobrown

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.

[Garduna]

I like my 6 speed thank you very much!

[footie]

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.

[mtechnik3]

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.

[mapezzul]

Originally Posted by mtechnik3

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.).

[burberry]

wow 8sp sounds fckin awesome

[mapezzul]

Originally Posted by burberry

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.