Transmission Trends 1

[SMUG]

Dear all transmission experts

Where do you see the emerging gearboxes like DSG,AMT,CVT , conventional Manual and Auto in the next five years for passenger cars.

Who will be leading the market and why?

What are the factors that are controlling this?

Does anyone know which one is more effecient or will be effecient?

Any ideas which is more cheaper and effecient?

Is there any factor of market and location?

Look forward to hear from you.

Ta

 

[mmenarry]

Next 5 years projections should be obtainable from current manufaturing projections - its a relatively short period.

From an "anecdotal" viewpoint from Ireland, conventional auto boxes are becoming more prevalent for your "A to B" cars, mainly due to huge increases in traffic congestion (stop-go conditions).

I can see the current crop of "semi-auto" boxes replacing standard manual transmissions in the mid to long term, with standard auto boxes starting to out-sell manual/semi-auto boxes over the same period.

One external pressure that I can envisage driving the trend would be the increased emissions controls that are coming through - I would expect auto boxes of some description being used to some extent to keep engines in the "efficient" rev range for compliance. It would also be a potential factor in twin-drive (e.g. Prius) transmissions.

Manual transmisions will predominantly be reserved for "sports" type vehicles, and recent trends there have been for semi-auto boxes, throughout the range from Ferraris to the humble VW Golf.

Just my 2c though!

M.

 

[SMUG]

Useful comments

What I have noticed is that DSG is becoming emerging technology in Europe rapidly specially vehicles on VW platform engines.

Is that same in North America? What about Japan and Asia?

Can CVT compete against DSG?

What is the future of conventional Automatics?

 

[GMIracing]

"Where do you see the emerging gearboxes like DSG, AMT, CVT, conventional Manual and Auto in the next five years for passenger cars."

If this isn't the multi billion dollar/euro question that everyone in the industry wants to know. But, in short simple descriptions...

DSG, everyone wants one, but nobody wants to pay what they cost to make.
AMT, most high volume systems are slow shifting, but they are improving, they won't grow that quickly over the next 5 years
CVT, complex, expensive, usually very torque limited, they also fell short of their predicted efficencies. With any luck, these will dissapear
conventional Manual, not much new tech here.
slushbox Autos, there will be some drastic advancements here. 6 speed is almost the min gears these days, and Lexus started production with a 7sp. Who is to know where the limit is? The fuel econ will never match a standard manual.
Hybrids, you forgot this "little"

"Who will be leading the market and why?"

How do you define market leader?

General Motors powertrain, there are approx 3-4 million of their transmissions being produced a year, and who knows how many 4L60s are out in the customer's hands. They know how to make them cheap and how to make them by the 100s. But their transmissions haven't exactly been the technology leader.

outside of the OEMs internal powertrain groups, you have ZF, Aisin, and Jatco all fighting for outsourced products. When an OEM finally decides to outsource a high value componet, like a transmission, it can get ugly. This is big business.

"What are the factors that are controlling this?"

Costs, mass, packaging, consumer preferences!, federal regulations, durability, performance (eff, shift time, shift smoothness), etc.

"Does anyone know which one is more effecient or will be effecient?" "Any ideas which is more cheaper and effecient?"

Standard Manual for both.

"Is there any factor of market and location?"

This could be another quite long question to answer. The short answer, yes location plays a factor in the market.

More in detail, Americans don't like to shift. Europeans like things complex, efficient, and working perfectly. Japan is trying to outcomplicate the Europeans, and they are getting good at it. Korea's powertrains will become bulletproof after receiving mountains of product durability feedback from their 100k mile warrantys. Everyone wants to know about China, i do also. UK and Australia still shift manuals with the left hand. Antartica still has a very small automotive market... but with global warming, who knows?

These views do not reflect the views of management.

To summarize, find a library that has back copys of Automotive Engineering, find a big cup of coffee, and go do some research.

 

[tbuelna]

With the increasing adoption of various hybrid technologies (hydraulic, pneumatic or electric) the need for the torque converter for starting goes away, and so does the conventional AT. The efficiencies of CVT's is low, they are expensive and lack durability, so they will likely soon disappear.

The future lies with the AMT or DSG type transmission designs, since they provide the best blend of cost, reliability and efficiency.

 

[Ataloss]

GMIRacing said: "6 speed is almost the min gears these days, and Lexus started production with a 7sp. Who is to know where the limit is?"

Actually Lexus skipped right over 7 speeds and just started production with an 8 speed automatic in their LS series.

Bob

 

[GMIracing]

Ataloss - you are right, the Lexus is an 8 speed. Mercedes-Benz has the 7 speed transmission.

tbuelna - i agree that with the new sytems currently being developed, it will eventually cause the end of the traditional automatic transmission... but I do not think this will happen within the next 5 or 10 years.

 

[patprimmer]

I still question the need for so many gears, especially when the torque multiplication of a torque converter is considered.

Efficiency gains by having the option of keeping the engine operating in a narrow rev range or having the ideal gearing for power, cruise or economy under vastly differing conditions will be offset by increased rotating weight. I do wonder if they are going past the point of no return (technically speaking that is).

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[crysta1c1ear]

drive by wire
erodes the distinction between manual and automatic
friction launch (no torque convertor, no clutch pedal)
allows vehicle to coast at times
power shift (eg dual clutch)
thus improving acc. c/w existing manuals
integrated starter generator / alternator starter giving
start stop functionality
electric only low speed driving possible, thus enabling
elimination of need for reverse gear
allowing automatic parking with electric power steer

But it will take more than 5 years.

 

[crysta1c1ear]

oh, and you can call it a hybrid if you want once ISG/BAS is in there.
Transmissions will do regenerative braking, and to keep electic storage to a mimimum, the power will be used as soon as possible to

1. keep oil pumps, water pumps, air con etc running while engine is off at lights etc, via starter motor running but not clutched to engine
2. restart engine
3. assist pulling away
4. smooth out any glitches if powershift is otherwise imperfect.

 

[SMUG]

Very interesting!Specially GMIracing for putting a flavour on the discussion?

What is technical benefit of DSG over AMT.The effeciencies suppose to be similar? Is it fuel consumption or comfort?
Why is DSG gaining more popularity than AMT even though the cost is but on the high side?

 

[crysta1c1ear]

What is technical benefit of DSG over AMT.The effeciencies suppose to be similar? Is it fuel consumption or comfort?

Comfort.

The efficiencies should be similar as the time spent shifting is small. However power interruption causes a nodding-dog effect as power is cut off and reapplied. When driving a manual the driver will smooth out the gear changes by easing off the accelerator before the shift and then reapplying the accelerator smoothly after the shift.

An AMT may interrupt the power at inopportune moments, eg when flooring the accelerator to overtake; a moment when a power interruption can be disconcerting to the driver, on the wrong side of the road with one vehicle next to him and maybe another coming towards him. This makes an automated manual maybe less comfortable than a real manual.

In a situation like that, a powershift gearbox can be well appreciated by the driver. Maintaining power during the shifting process should be more comfortable than a manual in theory.

 

[RossABQ]

Maybe not exactly to topic, but I have to wonder what consumer reaction is going to be to the cost of repairing any of thse 6/7/8 speed autoboxes 5 years down the road? A typical American 4-sp/lock-up FWD rebuilt trans costs $2k now, I've heard Honda 4-sp's are $4500; Audi Quattro box over $10k; god knows what a Lexus box costs! Will the consumer really take out another loan to get it rebuilt when 5th and 6th take a dump on the freeway ?!

My guess is this is a trend that may be short-lived...