Some companies like Volkswagen have decided to ditch the conventional automatic transmission for an all-twin clutch offering when it comes to a gearbox for those who do not want to bother with shifting and clutching, but many companies still swear by the automatic transmission with planetary gearsets and a torque converter as they usually offer much smoother shifts and thus are usually more suited for a comfortable drive.
Twin clutch and single clutch automated manual transmissions are catching up in terms of smoothness of shifting but the torque converter is also making progress when it comes to shift speed and fuel efficiency. ZF Sachs recently celebrated the 20 millionth torque converter to roll off its Schweinfurt plant.
The latest in ZF’s torque converter technology is the use of twin torsional dampers in the torque converter to allow the lock-up clutch to close at an earlier point in time. This results in faster shift times and better fuel efficiency due to the fact that the mechanical linkage thanks to the lock-up clutch is active more often rather than having power transferred through the oil. This quick-shifting gearboxes have appeared in some higher end BMW vehicles such as the BMW X5.
So yes, conventional automatics apparently aren’t going to disappear anytime soon, with ZF Sachs recently investing another 80 million Euros at its Schweinfurt plant to expand capacity. The plant will also be making ZF’s new 8-speed automatic transmission, that’s said to be making a production appearance on an upcoming V12 760i version of the F01 7-Series and a future Rolls Royce.
Though ZF appears to be committed to improving and pushing the limits of how far the conventional auto can go, ZF will also be venturing into the world of dual clutch transmissions. Two twin clutch boxes are said to be in the works – the 7DCT50 and the 7DCT70 which seems to indicate 7-speed units. Too bad it missed the M DCT boat – BMW’s 7-speed twin clutch box is sourced from Getrag, which traditionally supplies manual boxes to Munich.