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      12-29-2012, 11:44 PM   #1
sard
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Anyone have their DCT downshift two gears instead of one?

Anyone ever pull their paddle to downshift only to have it actually skip 2 gears down instead of one with a single pull? I've had this happen a few times. 2008MY.
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      12-30-2012, 12:35 AM   #2
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I think one thread would have been sufficient..lol
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      12-30-2012, 12:49 AM   #3
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Sorry. On iPhone and it tweaked out
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      12-30-2012, 04:49 AM   #4
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Read the manual on kick-down and pulling the downshift pedal.
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      12-30-2012, 04:27 PM   #5
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I actually do 3 pulls down on a very regular basis on the freeway. I just click it 2 or 3 times quickly. Sometimes I do the "hold the downshift paddle and press accelerator past the "click" point" but its more fun to just chuck a couple clicks and gear down, let it blip and than rocket off
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      12-30-2012, 06:09 PM   #6
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Quote:
Originally Posted by Munit
I actually do 3 pulls down on a very regular basis on the freeway. I just click it 2 or 3 times quickly. Sometimes I do the "hold the downshift paddle and press accelerator past the "click" point" but its more fun to just chuck a couple clicks and gear down, let it blip and than rocket off
The correct sequence is kickdown then pull the downshift pedal whilst in sequential mode.
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      12-30-2012, 06:25 PM   #7
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Quote:
Originally Posted by mlhj83 View Post
The correct sequence is kickdown then pull the downshift pedal whilst in sequential mode.
Guess I really need to RTFM..... what is the result after that sequence?
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      12-30-2012, 06:26 PM   #8
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I feel it's almost simultaneous, but I like to stab the throttle and pull the paddle then get off the gas a bit so I have the lowest gear ready.

When you hold the throttle down and pull the paddle to accelerate, there isn't much of surge or feeling of acceleration IMO. Feels very much like a regular auto in that regard. Either way, I think it would work much better without the detent/click point.

One thing I don't like is that right at 80, it gives you 4th gear instead of 3rd. So not the lowest gear possible. Just under 80mph though, you can get 3rd gear.
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      12-30-2012, 07:07 PM   #9
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Quote:
Originally Posted by mlhj83 View Post
Read the manual on kick-down and pulling the downshift pedal.
My foot is far from activating the kick down. Like just 10% down on the pedal.
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      12-31-2012, 01:51 AM   #10
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Quote:
Originally Posted by sensi09
I feel it's almost simultaneous, but I like to stab the throttle and pull the paddle then get off the gas a bit so I have the lowest gear ready.

When you hold the throttle down and pull the paddle to accelerate, there isn't much of surge or feeling of acceleration IMO. Feels very much like a regular auto in that regard. Either way, I think it would work much better without the detent/click point.

One thing I don't like is that right at 80, it gives you 4th gear instead of 3rd. So not the lowest gear possible. Just under 80mph though, you can get 3rd gear.
Yup, you are using the multi-downshift function as intended i.e. throttle and kick-down button fully depressed and then pull the downshift pedal once.

I too would have preferred if DCT picked 3rd gear instead of 4th but I suspect BMW M programmed a level of safety into this multi-downshift function at higher speeds to prevent too much engine braking (if you suddenly decide to lift off throttle just as DCT selects 3rd gear) or rear wheels breaking traction under acceleration. Manually selecting 3rd gear at that speed and then applying the throttle is much more controlled, thus safer.


Quote:
Originally Posted by sard
Quote:
Originally Posted by mlhj83 View Post
Read the manual on kick-down and pulling the downshift pedal.
My foot is far from activating the kick down. Like just 10% down on the pedal.
If pulling the downshift pedal once - without kick-down button depressed - results in multiple downshifts, then there is a fault somewhere, which you should demonstrate to the dealer ASAP to get it rectified. It might just be a poor electrical contact point on the downshift pedal that momentarily loses electrical contact when the pedal is pulled, and then regains electrical contact, thus interpreting this as 2 pulls of the downshift pedal.


Quote:
Originally Posted by skypx
Quote:
Originally Posted by mlhj83 View Post
The correct sequence is kickdown then pull the downshift pedal whilst in sequential mode.
Guess I really need to RTFM..... what is the result after that sequence?
As stated in my replies above, DCT downshifts multiple gears in sequential mode, so you don't have to pull the downshift pedal multiple times. This function does have its benefits, but I prefer to choose my gear first, then apply the throttle, as it's safer than having a fully depressed throttle while DCT automatically downshifts multiple gears for you.

Last edited by mlhj83; 12-31-2012 at 04:42 AM.
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      10-09-2013, 01:02 PM   #11
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The fact that you'd have to be at WOT to downshift makes that features useless to me.
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      10-09-2013, 01:17 PM   #12
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Quote:
Originally Posted by tdott View Post
The fact that you'd have to be at WOT to downshift makes that features useless to me.
yeah exactly, I can't wrap my head around it & I've never used it lol, by the time I press downshift after full throttle, I'm already @ the top of the rev range. I just downshift once or twice then hit it.

although in auto mode it works ok, still a lot of lag to go from 7th-4th, basically makes it as slow as a turbo'd car IMHO. I just manually select the gear I want a head of time, which I think is how you're supposed to be doing it :P
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      10-09-2013, 01:17 PM   #13
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Quote:
Originally Posted by mlhj83 View Post
The correct sequence is kickdown then pull the downshift pedal whilst in sequential mode.
I was under the impression that this isn't great for the clutch due to potential slippage?
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      10-09-2013, 04:03 PM   #14
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Quote:
Originally Posted by Jive View Post
I was under the impression that this isn't great for the clutch due to potential slippage?
There shouldn't be any clutch slippage as the computer controls the rpm and gearbox - you are simply giving it an instruction. This sequence is as per the handbook.
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      10-09-2013, 04:13 PM   #15
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      10-09-2013, 04:13 PM   #16
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Quote:
Originally Posted by mlhj83 View Post
There shouldn't be any clutch slippage as the computer controls the rpm and gearbox - you are simply giving it an instruction. This sequence is as per the handbook.
That doesn't mean it doesn't use or 'wear' the clutch.
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      10-09-2013, 07:18 PM   #17
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Quote:
Originally Posted by tdott
Quote:
Originally Posted by mlhj83 View Post
There shouldn't be any clutch slippage as the computer controls the rpm and gearbox - you are simply giving it an instruction. This sequence is as per the handbook.
That doesn't mean it doesn't use or 'wear' the clutch.
The computers involved ensure that the rpm is matched to the gear; the rpm will not be allowed to go beyond the optimal engine speed when downshifting to a particular gear.

Clutch slip happens when there is a speed mismatch between the rpm and clutch.
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      10-09-2013, 07:46 PM   #18
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Quote:
Originally Posted by mlhj83 View Post
Clutch slip happens when there is a speed mismatch between the rpm and clutch.
Everytime a gear is engaged there is some degree of 'slip' which in turn wears the clutch very slightly, during WOT shift in S5 or S6 that puts the most wear on the clutch.
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      10-10-2013, 05:10 PM   #19
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Quote:
Originally Posted by tdott
Quote:
Originally Posted by mlhj83 View Post
Clutch slip happens when there is a speed mismatch between the rpm and clutch.
Everytime a gear is engaged there is some degree of 'slip' which in turn wears the clutch very slightly, during WOT shift in S5 or S6 that puts the most wear on the clutch.
Of course, otherwise clutches would never wear out, but the above multi-downshift procedure won't cause any further wear than shifting at wide open throttle, which is what the gearbox has been designed to cope with - assuming the car is standard and functioning normally of course.
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      10-30-2013, 10:09 PM   #20
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Just got the M. What do you mean by kickdown. Sorry a newbie.
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