Thread: DCT tranny
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      12-02-2012, 06:22 PM   #31
gthal
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Quote:
Originally Posted by RPM90 View Post
I tried it a few times to see what it can do, and why one would need a 6 gear change.
It works on accel.

If you're in "comfort" auto mode, the trans will shift to 8th by around 40-45mph. Staying at that speed while crusing it's in 8th.
Then, stomp the throttle pedal past into the kick down resistance point, and the trans will down shift to 2nd, and it feels like one shift.

However, that one shift does seem to take just a smidge longer than any single down shift.

I think this capability is for fastest accel if one really needs it.
Still it does do what ZF claims it will do.
Very cool, and very fast.
Although this is a great feature of the 8AT it is one of the unfortunate downsides of auto transmissions... abrupt downshifts. I always, always, always drive in manual mode because I hate the kick down. Driving along in 7th gear, no power... give the car a bunch of gas and BAM downshift and ROCKET acceleration. It's OK on the highway but around town I don't like it. In manual mode, there are no surprises. This is really just personal preference having driven MT cars for 20 years and now having my second without a clutch pedal. Manual mode gives a little more control than full auto... hence full auto not needed

That's why I like to understand how the "manual" mode in each auto works when buying cars because my transmission is never in auto. From everything I have read, it seems like the 8AT in the BMW is capable in manual mode which is a good thing.
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