ZF's successful 8HP 8-speed automatic transmission has been characterised by energy efficiency, lesser emissions and better ride comfort as well as dynamics since the start of production in 2009. All of the advantages are now even more pronounced in the second generation that initially is in volume production since July 2014 in the BMW 520d.
The new 8HP offers comprehensive further developments that range from lower drag torques and higher spread through to an improved torsional vibration absorption. Gradually, the new 8-speed automatic transmissions from ZF are being deployed in further models and with many automotive manufacturers worldwide.
"Our longstanding customer BMW is impressively demonstrating how to successfully make vehicles more efficient yet more dynamic at the same time," says Dr Jürgen Greiner, head of Passenger Car Transmission Development at ZF Friedrichshafen AG.
"Therefore, we are particularly delighted that the premium manufacturer is the first OEM to rely on the second generation of our 8-speed automatic transmission that, when it comes to these criteria, is also groundbreaking. Through many further developments, we have made the 8HP significantly even more efficient compared to the predecessor transmission - up to three percent in total."
The new 8HP entered volume production at the start of July in the BMW 520d as the 8HP50 version that is designed for torques of up to 500 Nm. In the future, the 8HP75 will be part of the ZF portfolio for drives with even higher torque of up to 750 Nm.
Gradually, all further automotive manufacturers to whom ZF has already supplied the 8HP in over 1 000 vehicle applications will utilize the latest generation of the 8-speed automatic transmission.
It is the reduction of the speeds in particular that demands transmissions with a higher spread which is the reason why ZF has increased it from 7.0 to 7.8 on the new 8HP by means of optimised gearsets. "This measure alone reduces the speed across all gears by 50 revolutions per minute on average and reduces fuel consumption by almost one percent," explains Jürgen Greiner.
