Quote:
Originally Posted by ThugzZ BunnY
please tell me one reason that anyone would prefer the dct over the 8 speed? neither has a clutch so the drive the same. I don't understand why people cry about this. also the 8 speed is more reliable.
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I have both the zf 8 in the x5m and the dct in the m3.
The drive experience is drastically different.
I have posted numerous times already, but the main points are
1. no immediate skip shifts. 3 gear downshift on the zf is 7-6-4, on the dct it is instant 7-4th.
2. zf8 downshifts can be rough, and smooth, it is inconsistent and depends on the speed and the rpm of the engine. the dct is almost always smooth. This is in S3 mode for both cars.
3. torque modulation- the zf will modulate torque to save the tranny on occasion, there is a noticeable dip in power during transitions. the dct snaps gears consistently.
4. heat- I have overheated my drive train 3 times on the x5m. I have never overheated my dct on the m3. The zf will simply ignore commands once this threshold has been passed. You will get a drivetrain malfunction on your display if prolonged. I would be interested to know if the new m5 sustains long track times without overheating the zf8. Hopefully it has better tranny cooling.
5. shift speed- on 1 gear requests, the zf is actually faster than the dct during normal below redline shifts. During WOT, the dct shifts harder and snaps gears, the zf will be more modulated- again both in s3.
zf also manufactures the PDK for Porsche which I have had the pleasure of driving, and the PDK is amazing and by far the best transmission. The devil is in the details and if you don't care, then it doesn't matter- but there is a clear difference between dual clutch transmissions vs torque converters.