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Land Rover to demonstrate latest technical innovation with the worlds frst 9 speed automatic transmission

Land Rover announced of the world's first 9-speed automatic transmission for a passenger car. The ZF 9HP transmission is specifically designed for transverse applications, and is one of the most efficient and technically advanced transmissions ever used in a production vehicle.

Land Rover is the lead partner on the project, working together with ZF who are widely recognised as the world leader in transmission technology.

Increasing the number of gear ratios from six to nine gives significant improvement in fuel economy and a corresponding reduction in CO2 emissions. Smaller ratio teps 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.

The 9HP is extremely robust and perfectly complements Land Rover's rugged all-terrain ability whilst delivering exceptionally high levels of refinement and efficiency. The lowest ratio in the 9HP is far lower than the existing six-speed transmission and is specifically designed for off-road use, towing and more extreme on-road conditions like gradients and altitude, giving the driver a heightened sense of control.

The innovative adaptive shifting system matches the driver's mood within seconds, sharpening up during brisk driving then slipping seamlessly into a more economical regime just as quickly when taking a more relaxed approach. Curve Mode, longitudinal acceleration and pedal position all control upshift prevention.

Fast-Off mode measures the rate of throttle release, anticipates further requests by the driver for high power, then holds the gear if necessary. If the driver requests a downshift when the vehicle is travelling too fast, the transmission will remember the request and make the shift when the speed drops to an appropriate level.

The 9HP is a masterpiece of packaging and despite the extra three gear ratios is only 6mm longer and weighs 7.5kg less than the outgoing six-speed transmission. The small package space is achieved by a number of innovative design features including a new hydraulic vane-type pump which also contributes to improved efficiency, two, patented, dog clutches replacing bulkier conventional clutch packs, and an Intelligently Nested gear set.

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