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      01-27-2012, 08:57 AM   #71
epiphone3
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Drives: 2013 BMW X3 35i
Join Date: Oct 2005
Location: Calgary

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Quote:
Originally Posted by paul386 View Post
This isn't true. The ZF 8HP has a locking torque converter, only 2 shift elements, and a fancy hydraulic control unit. There are other cool technologies including the hydraulic accumulator that makes start - stop possible. This should be plainly evident by the automatic transmission being more efficient in city and highway driving.



Diesel fuel is expensive in the US because of taxes that are higher than taxes on gasoline. Diesel cars are expensive because of emission requirements.



And cost more....
Put the same car with an auto and with a manual on the dyno and the manual puts more power to the wheels.

The auto is less efficient in terms of losses. Having extra ratios is what allows the transmission to keep the engine revs lower in both city and highway driving hence yielding lower fuel consumption.
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