ZF Launches World’s First 9-Speed Automatic Transmission


It was not a long time ago that 6-speed automatic gearboxes were a privilege largely enjoyed by top of the range models. However, in their quest for efficiency, manufacturers have quickly moved on to 7- and 8-speed boxes which trickle down the line to even the smallest models in the range (e.g. the new BMW 1-Series).

But ZF has outdone them all by launching the world’s first 9-speed automatic transmission for passenger cars in the VDI Conference “Transmissions in Vehicles 2011”. The new gearbox, code-named 9HP and designed for cars with front-transverse drive, is available in two model ranges, can handle torque between 280 and 480 Nm (206.5 – 331.9 lb-ft) and can be combined, according to each manufacturer’s requirements, with different stop-start systems, hybrid and all-wheel drive applications.

According to ZF, the 9HP offers fuel savings up to 16% compared to today’s 6-speed automatic transmissions in front-wheel drive cars thanks to the extremely high total spread of 9.84 and the high number of gears that allow the engine to run in the most fuel-efficient speed range. For example, in 9th speed, you can travel at 120 km/h (75mph) with the engine running at just 1,900 rpm, compared to 2,600 rpm in a 6-speed auto.

But the 9HP offers more than better fuel economy: even though it uses a standard torque converter instead of the double-clutch configuration which has become increasingly popular, ZF states that it has designed all components for faster response and shift times that are “actually below the threshold of (the driver’s) perception”.

ZF’s new gearbox has been developed as a “construction kit”, making it possible to be installed in a variety of configurations. To achieve this, the company has developed a new all-wheel drive system in which the rear axle drive is decoupled under normal driving conditions and is actuated only when required, reducing fuel consumption by 5% compared to permanent all-wheel drive systems.

The 9HP is, by default, compatible with stop-start systems without the need for an additional oil pump, and can also be used in parallel hybrid architectures, in which case the torque converter is replaced by an electric motor.



Anonymous said... »June 11, 2011

It seems unusually small compared to other 6, 7, or 8 speed transmissions.

Anonymous said... »June 11, 2011

I predict in only a few years Ford or Hyundai will be one the first automakers to offer a nine speed in their mid range models like the Fusion or Sonata, esp Hyundai since they have stated they want all their passanger cars to reach 55 mpg in the coming years.

William said... »June 11, 2011

Where does it end? Get it over and go to CVT.

Anonymous said... »June 12, 2011

test drove the S-merc couple of months ago, it has 7 speed forward and 2 reverse, the tranny kept busy hunting for the right gear, compeletly annoying, i dont see a point from anything more than 5-6 spd tranny

Anonymous said... »June 12, 2011

Manually shifting through 9 gears will too busy for driving. It's not practical at all. Unless there is no manual shift option, then it doesn't matter how many gears it has.

I'd rather have 7-speed at most.

Anonymous said... »June 12, 2011

Can give a long engine life too. Less wear and tear when you have such a wide spectrum. Hmmm debatable. Automatics can be the the only go for such transmissions. Nevertheless another door... may be to efficiency.

Anonymous said... »June 13, 2011

The CVT with selectable gear ratios can only be the future.

I dream of the day when the driver shall be given the right to choose on his own will - through a menu in the dassh panel - the number and the ratios of every separate gear and drive either way or another, smooth CVT-like or conventional-like-simulatedthroughCVT drive .

Anonymous said... »June 13, 2011

I've driven several CVT equipped cars and I don't like them at all. Can't believe so many people here actually like CVTs.

As for the 9 speed, as long as the shifting is quick and unnoticeable to the driver it should work better than the aforementioned transmission.

BTW Chrysler has already announced that their cars will get this ZF 9 speed very soon(upcoming months). Not Ford nor Hyundai. Not bad for a company that most people claimed would have been gone by now.

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