Second iteration is claimed to be 3% more efficient.
Transmission major ZF Friedrichshafen AG has announced volume production of the second generation of its successful ZF 8HP 8-speed automatic transmission. The company has revealed that new gearbox is in volume production since July 2014 with the BMW 520d being the first beneficiary.
According to the German drivetrain specialist, the first gen 8HP is being used in over 1,000 vehicle applications across several automotive brands. All these models will be eventually updated with the improved transmission.
The variant used by the BMW 520d is the 8HP50 which is designed to handle torque outputs of up to 500 Nm. A more rugged variant 8HP75 for drives generating torque of over 750 Nm would be introduced at a later stage.
The new ZF 8HP is optimized to support the recent trend of engine downsizing which is usually accompanied by downspeeding (reduction of engine speed) with maximum torque applied at an early stage. The downspeeding, ZF says, demands the transmission to have a higher torque spread and that is why the upgraded gearbox has a spread of 7.8 against its predecessor's 7.
Further, additional springs have been fitted to the shift elements to reduce the drag torque. This and several loss-reducing measures have resulted in an overall increase in efficiency of 3% over the older version.
Consult the press release below for more details on the efficiency enhancing measures incorporated in the new ZF 8HP.
New ZF 8HP 8-speed transmission enters volume production in the BMW 520d - Press Release
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