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ZF opens passenger car transmission plant in the US; emphasis on 9-speed automatics

Manufacturing 8-speed automatics at Gray Court. Click to enlarge.

ZF Friedrichshafen AG has officially opened its new plant for automatic passenger car transmissions in the US. Located in South Carolina, ZF Transmissions Gray Court, LLC will produce about 1.2 million transmissions at this plant annually; this includes 400,000 8-speed and 800,000 9-speed automatic transmissions (earlier post). The new plant expands the existing capacities at the Saarbrücken location to produce 8-speed automatic transmissions.

So far, ZF has invested around €300 million (US$399 million) in building the new location, which is around 130 kilometers (81 miles) north-west of Columbia. A total of approx. €450 million (US$598 million) is planned for investment into the new location—the largest single investment in the almost century-long history of ZF, emphasized Dr. Konstantin Sauer, ZF Board Member responsible for finance and the North American region.

The 90,000-square-meter facility will be expanded to a total of around 130,000 square meters by 2016.

We are very confident that in addition to our current customers, Land Rover and Chrysler, other automotive manufacturers will join in and benefit from the advantages of our 9-speed automatic transmission.
—Dr. Konstantin Sauer

Land Rover announced its use of the 9HP transmission at the Geneva Motor Show in March (earlier post); Chrysler announced its application of the 9-speed in the 2014 Jeep Cherokee at the New York International Auto Show (earlier post).

The ZF 9HP 9-speed. Source: ZF. Click to enlarge.

The new 9-speed transmission is specially designed for passenger cars with front-transverse engines. Smaller ratio steps give improved response during acceleration, improved shift quality, drive and refinement. The higher top gear not only reduces fuel consumption but the lower engine revs improve comfort and reduce noise when cruising at high speed. ZF says that in real-world testing at a constant speed of 120 km/h (74.5 mph), the 9HP reduced fuel consumption by 12% in a gasoline-powered SUV and by 16% in a diesel-powered SUV.

Features of the 9HP include:

  • Planetary gearset with 9 speeds, 4 simple gearsets, and 6 shift elements. Gearsets are nested to save space.

  • Wide transmission ratio spread (nearly 10) with small ratio steps.

  • The first use of interlocking dog clutches in a passenger car powershift transmission.

  • Torque converter with excellent vibration and oscillation isolation for optimal comfort during starting (driveoff) and shifting.

  • Low engine speeds for increased fuel savings.

Since around three quarters of all passenger cars worldwide are fitted with this [front-transverse] drive configuration, I see great potential for our new product—especially in North America.
—Dr. Konstantin Sauer

ZF chose South Carolina because numerous automobile manufacturers and suppliers are already located in the area, and the local government provided a number of great opportunities to build a new facility. In addition, Piedmont Technical College established a new facility near ZF to aid in the training of a skilled workforce. With Clemson University in the area, it provides a great opportunity to recruit future engineers. Furthermore, the new ZF US employees have been trained in the subtleties of transmission assembly by experienced, specialized ZF workers from Saarbrücken via the “Buddy Program”.

The employees, trained internally through this program, now work as multipliers in Gray Court and are passing on their knowledge to the subsequently recruited US colleagues.



For the price of a 9-speed transmission one can imagine many ebikes or maybe a 2-seat MG Midget-sized EV.


Ever notice how complicated an internal combustion engine and automatic transmission really is with all those parts and spinning gears, etc?

Ever notice how simple a direct electric motor drive line is?

Solve the battery range problem for EVs and you can save yourself from needing 7 speeds and all that complication that goes with ICEs.


The gearboxes are very complex, but people have got very good at making them as they have been doing it for > 100 years.

+ @Lad, Oerlikon seem to think we need a 4 speed for electric motors (but they are selling them).


What we may need is a planetary gear CVT for an EV, if patents don't get in the way.


A two e-motor AWD EV could do a good job without multiple speed transmission. Use both motors for acceleration + hills and automatically select the most efficient motor for various cruising speeds.


Most differentials have about 3 to 1 reduction, so front, rear or eAWD is possible. With eAWD you can have smaller motors that could be more efficient.

An electric motor is not 90% efficient over it total operating range. Low RPM high torque high current can be significantly less efficient.


If the transverse 9HP is reducing consumption 12-16% and the rear-drive tranny/driveshafts will lose 8-15% depending on how many ring & pinions its put through...why even build it?

Surely electric motor technology can make virtually anything cruise like a golf cart on RWD at 10-20 mph. And start/stop can kill ICEs when unneeded.

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