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VW Debuting 7-Speed DSG in Golf and Golf Plus

7dsg
The 7-speed DSG offers improved fuel consumption and lower GHG emissions compared to other transmission options—even besting the manual. Click to enlarge. Source: VW

The new Volkswagen 7-speed DSG automatic transmission (earlier post) is now available in selected countries in the Golf and Golf Plus with the 1.4 TSI and 1.9 TDI engines. In the new 7-speed, the lower gears are more closely spaced, improving in-gear acceleration to aid in overtaking maneuvers, while the higher gears are lengthened to reduce loading on the engine and maximize economy.

The new 7-speed automatic transmission is the first DSG for front-traverse installation. It is also the first with a dry sump. This not only saves considerable weight and improves the efficiency of the system but also makes the new gearbox more compact. The maximum torque that can be transmitted is up to 250 Nm.

The new unit will initially start series production in the Golf and Golf Plus, and is available for the 1.4 TSI engine (90 kW), previously only available with a manual gearbox, and for the 1.9 TDI engine (77 kW).

As with the six-speed DSG gearbox, of which more than one million have been produced since launch, the new seven-speed system features a hill-hold function to aid starts when the vehicle is on an incline.

Fuel consumption figures for the Golf / Golf Plus 1.9 TDI with the 7-speed DSG are 0.7 liters per 100 km lower than they are with the 6-speed DSG. In the Golf hatchback, compared with the six-speed manual version, the new seven-speed DSG brings a 10 g/km CO2 saving (down from 149 g/km in the manual to 139) and a fuel consumption improvement of 0.4 liters per 100 km (from a combined 6.3 l/100km for the manual to 5.9 l/100km for the 7-speed DSG—about 40 mpg US).

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Comments

Harvey D

If VW (and others) can reduce CO2 and fuel consumption that much with 7-speed automatic vs 4-speed automatic, why are most of our North American gas guzzlers are still using 4-speed automatic transmissions?

Have we all been tricked or lied to for generations?

Winston Churchill realized that 60+ years ago. We, the people, have taken 50+ years to see the evidence.

It is no wonder that the Big Three local market share has been going down for the last 10+ years.

Thomas Pedersen

Well, Harvey, I suspect that most NA gas guzzlers have more than 250 Nm peak torque. But you're right, why has this not been developed for bigger cars? I see no fundamental reason why that should not be possible. Ah, now I get it - the dry sump transmission, which gives the high efficiency, is only possible at this torque level...

Unless you have a big car, 250 Nm goes a long way with a seven-speed gearbox. The 22% saving in fuel will also be felt during acceleration.

At the moment, I'm considering getting an Audi A3 Sportback with either the 1.9 TDI or the 2.0 TDI. The 1.9 supposedly has better fuel economy (EU rating), but I suspect the 2.0 has better economy at 80 mph (speed limit on Danish highways) due to higher gearing (the 1.9 is a 5-speed manual shift and the 2.0 is six-speed manual, or 6-speed DSG). That and the fact that the 2.0 is much more fun has me leaning towards the 2.0 model. However, this gearbox, if available, might push me back to the 1.9, which now comes in a new version with 11% better fuel economy... Ahh, the dilemmas we face in the industrialized world... ;-)

The real benefit in terms of fuel economy with an automatic shift is that it allows a higher gearing ratio in the top gear. With a manual shift you don't want to have to shift down in the top gear to overtake someone on the highway. As a result of that, carmakers lower the highest gear ratio. But with an automatic shift, there is no problem with cruising in 7th in low revs at almost peak torque and then downshift immediately with the flick of a paddle (or automatically) when more power is needed.

shane

The reason this, and many other technologies, aren't widely deployed in the US is due to a lack of serious consumer interest until lately. Just like in other countries, at the end of the day it boils down to cost. When fuel prices were ~$1.50/gal noone really cared. Even at $3/gallon, there may be whining, but most often - to a new car buyer that only intends to keep a car for 2-3 years - the added costs don't make sense - they'd rather stay with "known" technology. The good news is, with gas costs up, and new legislation - things are starting to change. Some people like the new technology, and want something new - but most people want a lower cost car that does what they want.

RhapsodyInGlue

Interesting how people take advantage of every little trick to try to fudge numbers. While it is true, taking the emissions numbers at face value, that the 4 speed automatic produces 22% more than the new transmission. It is not true that the new transmission produces 22% less. (100-122)/122 gives an 18% reduction. That simply is the way math works... at least back when I learned it.

I give the marketing guy who did the graph an F on the assignment and suggest he repeat 4th grade.

Harvey D

shane:

Those of us looking for a very low cost car may be interested in the Tata-Fiat $2500 vehicle project.

As it will be much lighter and not over powered the fuel economy should be better and GHG/CO2 much lower.

CO2 should be well under 100 gm/Km. An electric version will probably come soon afterwards.

rca

Chrysler is launching a new dual clutch 6 speed automatic transmission in the front wheel drive minivans and mid size cars in 2009. The information available at this time says that it will provide a fuel economy improvement of up to 6% with a 1 to 2 second reduction in 0 to 60 times. It is highly likely that similar transmissions will be launched in all vehicles over time.
Ford is also launching a 6 speed dual clutch transmission in 2009 but I don't know any of the deatils.
These transmissions will be mated to new engines including the new Phoenix V6 at Chrysler which includes cylinder deactivation, variable valve timing and direct injection and possibly other technologies.

wintermane

The reason they didnt do it before is simple.

1 They couldnt. They simply didnt have the materials and tech to make a small enough transmision with that many gears.

2 The cost of us workers is about 2500 prt car.. the most spendy items in a car are engine and trans. So a good 2000 had tp come out there.

3 THEY DID MAKE THEM.. but sooo few people paid more for more economy that those options stayed mostly unknown... Example... the ford econoline van also came in a soecial version with a second overdrive gear...waay back in 75 or so.

4 Up until bas and hybrids... stop and go freeways trumped the better trans as they mostly has been concentrating on improving cruising speed mpg at 75 mph. And that also got hosed big ti,e by the 55 law.

Brian P

Pretty sure BorgWarner owns the dual-clutch transmission technology; they manufacture VW's DSG transmissions and are probably going to be manufacturing the same technology for others.

My dad has a VW Jetta TDI DSG - it's very good. I have the same car but 5 speed manual. Consumption is about the same (i.e. there's no penalty for the automatic).

Harvey D

wintermane:

Are you sure that a lightweight 7 speed transmission could not be designed and built 40+ years ago? Why do I feel that we have been taken for granted for decades.

Would CVT perform as well as 7-speed units?

The same could apply to AC and Heatpumps. Our old heatpump had a SEER of 9 and our new one has SEER 23. What a difference in efficiency. Power consumption and noise are much lower. By the way, we paid less for this new super high effciency unit than the old low efficiency unit 12 years ago.

Now, will this new unit with its Inverter variable speed motors, last as long or longer? Time will tell. It sohould last longer because it turns much slower most of the time. This new unit will pay for itselve in about 8 years due to the 60+% reduction in power consumption. The extra very low noise + much more steady temperature are free side benefits.

jw

As has been stated by other already, the 6 speed automatic has become commonplace as of the last few years, the 5 speed has been common for 10 years or so. The costs involved in the design and production of an advanced transmission such as the new 6 speeds and now this 7 speed are tremendous. The new fwd 6 speed being installed in Ford and GM cars is a joint venture between the 2 manufactures. As for CVT technology, I know that ford is moving away from it because of its failure to produce the expected gains in fuel economy versus a 6 speed automatic unit as well as tremendous customer dissatisfaction with the noise and lack of shifting. The amount of torque the units can be designed to tolerate is a problem for vehicles sold in the US. People here demand torque and horsepower over economy. There is also a move into RWD 6 speed units in SUV’s and trucks. It was a simple matter of economics that dissuaded the manufactures from designing and installing these units in the large vehicles. Why would someone pay $1500 (us) more for a new unproven 6 speed transmission versus the tried and reliable 5 speed for a 3 to 6% increase in fuel economy in a world of sub 3 dollar fuel? Adam Smith’s invisible hand guided the consumers and the manufactures to do what as in everyone’s self interest.

Brian Strom

I once had an Audi CVT loaner car for a day. I got it out on the highway and bumped it up to about 90, and though I don't remember the exact ratio, it was somewhere around 2800rpm's. Seems that might work as well as a 7-speed.

Rafael Seidl

VW had some sort of temporary exclusivity clause when it launched the first vehicles withBorg Warner's dual wet clutch technology. The dry clutch variant announced here expands the option into models with more modest gasoline engines. The seventh gear is possible because the dry clutches are shorter than the wet ones. The associated transmission ratio is most likely an overdrive for efficient and quiet highway cruising.

Harvey D

jw:

Assuming we drive about 15000 miles/year with 20 mpg (avg) vehicles @ $3.00 gal. = $2250 a year for gas.

A 22% fuel economy would mean about $500/year/vehicle. You could recouperate the extra $1500 for a 7-speed transmission in only 3 years.

In EU and where gas is $6/gal., it would take only 18 months to recouperate the extra cost.

If you add the value of the 2 tonnes/year reduction in CO2 emission = another $200/year, the total extra cost could be recouperated in about 2.2 years in USA and in about 16 months in EU.

It seems that, based on cost, the 7-speed transmissions should installed in all cars and light trucks. The winners would be us (the buyers).

Raymond

I do think more and more vehicles are going to new, sophisticated automatics to improve (especially) fuel efficiency at higher speeds.

One transmission that could get serious consideration is the Antonov AAD six-speed automatic, which is much lighter than a conventional automatic transmission. We could see smaller vehicles equipped with this transmission within the next few years.

CVT's have gotten a lot better lately, especially with improved electronic programming to reduce the "slipping clutch" feel of older CVT units. Also, the latest CVT's can withstand the torque of higher-powered engines, too.

Stan Peterson

CVT have an infinite number of "gears" and should be most efficient. But the losses in keeping hydraulic pressure on the pulleys and drive belts saps energy.

Drivers are just not prepared by experience to understand the benefits a CVT is bringing and tend to want to "shift by ear" as experience has taught them. Drivers think the CVT is "slipping" and/or "droning" when it is performing. Hence it has not been well received.

Auto manufacturers are abandoning the more advanced CVT for something less efficient, but more familiar.

litesong

Stan's accessment of the public's reaction to the CVT & its 'performance' hydraulic pressures is correct.

CVTs & Twin Clutch trannies are the coming tech, tho their birthing pains have been long. One hundred years of clunky shifting transmissions have locked people's perceptions that movement can only be made by jerking forward.

One must approach the CVT like a propellor airplane. Set the rpms & accelerate. Like an airplane propellor drawing you down the road(runway), there is no jerky shifting. Like an airplane, the rpms stay the same. Unlike an airplane if you drive for economy, the engine is hush quiet, even & vibrationless.

My Dodge Caliber's CVT hydraulic pressures under heavy load approach 1000 pounds per square inch. Sure, the CVT can't get the theoretical 6% increase in MPG compared to 4 speed automatics with such high pressures. However, I'm a feather footer & avoid those pressures. The 3000 to 3300 pound Caliber is not economical. But I'm overall averaging 31.4MPG, averaging 32.7MPG on trips over 4000 foot mountain passes, & have a flat highway high of 35.6MPG....& I don't slow people who drive behind me....accept for the racers.

Travel over the changing slopes of those 4000 foot mountains is elegant & magic carpet smooth. It is vehicle motion like it always was meant to be. But people have gotten so used to jerky progress while transporting themselves, that ultra smooth motion seems wrong.

Jorge

I think some persons would prefer DCT transmissions over CVT because of the "feeling" that DCTs are more reliable or dependable than CVT.

litesong

Hi Jorge...The rubberized CVT pulleys which were the reliability downfall of older CVTs do not exist in the best developments of the CVT. Toyota uses a version of CVT in their Hybrids, Nissan is putting lots of CVTs in their cars, & if CVTs weren't reliable, Chrysler would surely exclude them from their lifetime warranties. I'm not here to put twin clutches up against CVTs, but tranny technology marches on & cars need not inefficiently jerk along anymore. Also, electric motors will give efficient performance without direct pollution impact to humans, noise & vibration, which are past societal perceptions of power.

All in all, jerking along, pollution, noise & vibration are now seen as inefficiencies that are passe.

Jorge

litesong,
I am not saying CVTs are unreliable, but the slippery feeling makes some people think that this technology is not well proven.
I had the chance to drive an Audi A4 multitronic (CVT) and a Jeep Compass CVT also.
I liked better the behaviour of the Audi transmission.
I think this transmission uses a special traction oil.

Harvey D

Sooo... are recent CVTs as fuel efficient as 7-speed transmissions?

Which one cost less to produce?

If performance + fuel economy are similar; production cost + resistance to rough usage over long periods + drivers acceptance may play a deciding role.

litesong

Hi Jorge...Slippery feeling? That is why I gave the airplane analogy. There is nothing wrong with the slippery feeling or rubber band effect. Its 100 years of jerking automobile motion that is the fault. Its time America got over it. As Abraham Lincoln said, we must think anew & act anew.

Harvey D...Under heavy acceleration, dry Dual Clutch trannies have to be more efficient than high hydraulic pressured CVTs whose pressures are needed to smoothly widen & narrow the CVT pulleys to activate 'shifting'. That is why my specific low performance, pressure avoiding feather footing delivered good MPG (for the Caliber).

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