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 Issues with Dry Dual Clutch Tranmissions, Ford Focus, Fiesta, VW or Any Other Cars

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TSSportyHandling
post Sep 18 2015, 07:57 AM, updated 5y ago

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I would like to draw experience of owners who currently own vehicles which come with DCT, particularly the dry clutch versions which was claimed to exhibit more "issues" in comparison with the wet versions. I am interested to know on the symptoms or characteristics that you have experienced in your car, especially if it requires your vehicle to undergo a clutch pack / assembly replacement due to leakage of the clutch. If your car has undergone the clutch replacement, I would like to know whether it is a permanent solution in that the issues associated with the transmission are eliminated completely for good, or the transmission exhibits the same issues after few months (or years) down the road.

For those who have had the clutch assy or clutch pack replaced at the service centre, I would like to know the symptoms you have experienced in your car. My experience with the Ford Focus is as follows :-

1. During low speed acceleration, the car is holding on to the gear and does not upshift as quickly as before. This is especially evident when driving the car in multi-level car parks or along roads with a lot of speed bumps in between. When the car is accelerating in say 2nd gear, the car does not upshift to 3rd gear and drags along, resulting in a louder sound from the engine. And when the gear finally upshifts, there is a rather unpleasant jerk(since the upshift occurs at a higher than optimal RPM). Similarly, when the car is decelerating, either the driver steps on the brakes or the car glides slowly with decreasing speed, the car stays in gear and is slow in downshifting, resulting in higher RPM. When the transmission finally downshifts, the car jerks.

2. The sound from the engine is louder when the transmission is upshifting during low speed acceleration. Previously when the car was new, the car was silent when accelerating from standstill. I can barely hear the sound from the transmission when the gears are changing. However, I now hear the sound from the transmission when the gears are upshifting. I believe this is due to the transmission holding onto the gear longer (as in point 1 above) which results in a louder sound from the engine at higher RPMs.

Basically these are the 2 most apparent aspects that I experience in my car before the guys at the service centre informed that there is leakage in the clutch of my car which requires the clutch pack and assy to be replaced.

I would appreciate some experience not only from Ford but VW or any other car owners who have encountered issues with the transmission, particularly the dual-clutch versions. Any information would be most appreciated.

This post has been edited by SportyHandling: Sep 18 2015, 08:00 AM
hardcorie
post Sep 18 2015, 08:22 AM

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dares jylova

This post has been edited by hardcorie: Sep 18 2015, 08:27 AM
dares
post Sep 18 2015, 09:27 AM

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I don't understand how slow in downshifting during deceleration would result in high RPM.

Anyway, for Ford Powershit, in my experience, juddering often occurs when it upshifts too early during low speed, light acceleration. Imagine driving a manual car and upshifting to 3rd gear at 20km/h, you'll get the idea. and the Powershit is VERY EAGER to upshift for fuel economy reasons....I often found my Fiesta in 4th gear by 40kmh. at these speeds in high gear, the clutch would slip so the engine won't stall easily, especially when there is not enough throttle (again, like half-clutching when driving a manual car), and this overheats the clutch. My only way to counter it is to throttle harder to ensure the clutch closes completely, but this would cause the transmission to think I am accelerating hard and holds the lower gear longer (up to 3k-4k RPM)

I'd imagine the new TCM they updated for you after your clutch replacement now does the same, it tries to hold the lower gears longer to reduce clutch slippage in low speed, and the expense of fuel economy and NVH.

This post has been edited by dares: Sep 18 2015, 09:43 AM
zweimmk
post Sep 18 2015, 10:29 AM

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VW DSG7

Symptoms:

- Jerky shifts at very low rpm (evident in traffic jams)
- juddering at 1st / 2nd gear. The whole car will feel like it's shaking, not unlike a manual car of the 90s when you upshift too early.

Clutch replacement:

All juddering symptoms gone. Jerky shifts at very low rpm still present but less obvious.

VW by default programs the DSG clutch to upshift to 2nd gear as soon as it is able to. In traffic jam condition, the gear will shift to gear 2 very quickly, even when it is not at ideal speed conditions. This results in very quick clutch wear.

Solution: Driving the DSG in manual mode and upshifting the gears yourself will drastically slow down clutch wear, particularly during traffic jam situations. Switching back to D mode can be done once you are in moderate or clear traffic.


dares
post Sep 18 2015, 10:36 AM

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QUOTE(zweimmk @ Sep 18 2015, 10:29 AM)
Solution: Driving the DSG in manual mode and upshifting the gears yourself will drastically slow down clutch wear, particularly during traffic jam situations. Switching back to D mode can be done once you are in moderate or clear traffic.
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The same solution suggested by some Ford Powershit owners: Drag the first gear longer using manual mode.
Jackofree
post Sep 18 2015, 10:49 AM

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Mine is 6 speed DSG which is wet clutch but did a clutch replacement under warranty last month. My gear changes slower after clutch replacement. Asked SC why is it like that, then technician said new DSG software is programmed to change gears slower to protect the gearbox. I think this is bullshit but no choice, I guess I'll ask another SC for second opinion. Because of this, my car feels slower than usual until I floor the pedal biggrin.gif
zweimmk
post Sep 18 2015, 10:56 AM

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The DSG6 wet clutch doesn't wear that easily. The design is different, or so I was told. That clutch has a rated torque load of 550Nm.

What the SC said isn't wrong, they usually program the TCU to run the hardware less aggressively to reduce wear. It's just like many people complaining about the car feeling less powerful after they claim their mechantronics or clutch etc.
zweimmk
post Sep 18 2015, 10:58 AM

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QUOTE(dares @ Sep 18 2015, 10:36 AM)
The same solution suggested by some Ford Powershit owners: Drag the first gear longer using manual mode.
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This actually is the best way to drive the car - in manual. You get to control the power and when you want the torque to come in. Depending on how you look at it also, it's either a pro or a con. I've been driving my car in almost complete manual mode after I did a clutch replacement. It just feels better that way.
TSSportyHandling
post Sep 18 2015, 11:16 AM

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QUOTE(dares @ Sep 18 2015, 09:27 AM)
I don't understand how slow in downshifting during deceleration would result in high RPM.

Anyway, for Ford Powershit, in my experience, juddering often occurs when it upshifts too early during low speed, light acceleration. Imagine driving a manual car and upshifting to 3rd gear at 20km/h, you'll get the idea. and the Powershit is VERY EAGER to upshift for fuel economy reasons....I often found my Fiesta in 4th gear by 40kmh. at these speeds in high gear, the clutch would slip so the engine won't stall easily, especially when there is not enough throttle (again, like half-clutching when driving a manual car), and this overheats the clutch. My only way to counter it is to throttle harder to ensure the clutch closes completely, but this would cause the transmission to think I am accelerating hard and holds the lower gear longer (up to 3k-4k RPM)

I'd imagine the new TCM they updated for you after your clutch replacement now does the same, it tries to hold the lower gears longer to reduce clutch slippage in low speed, and the expense of fuel economy and NVH.
*
I cannot verify for sure at the moment since I don't have the car with me now, whether it is a case of slow downshifting or high RPM. But one thing is for sure. When the car is decelerating, slowing down in low speed in heavy traffic or multi-level car parks, when the car is gliding from say 30km/h to 20km/h, the sound, either from the engine or transmission(not sure), gets louder. The sound is akin to a dragging sound, the gear is dragging and it gets louder when the car is slowing down.
dares
post Sep 18 2015, 11:26 AM

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QUOTE(SportyHandling @ Sep 18 2015, 11:16 AM)
I cannot verify for sure at the moment since I don't have the car with me now, whether it is a case of slow downshifting or high RPM. But one thing is for sure. When the car is decelerating, slowing down in low speed in heavy traffic or multi-level car parks, when the car is gliding from say 30km/h to 20km/h, the sound, either from the engine or transmission(not sure), gets louder. The sound is akin to a dragging sound, the gear is dragging and it gets louder when the car is slowing down.
*
Sounds like engine braking in low gear, with the clutch fully closed. Pros of this is the transmission downshifts responsively according to speed, that means if you want to re-accelerate it will be in the right gear. Cons is, louder engine noise and possibly jerking.

From what you described, I think the main strategy for the new TCM is to reduce clutch wear at low speeds. If you want, you can try asking SDAC to reflash the old version to your car.

This post has been edited by dares: Sep 18 2015, 11:28 AM
TSSportyHandling
post Sep 18 2015, 11:30 AM

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QUOTE(zweimmk @ Sep 18 2015, 10:29 AM)
VW DSG7

Symptoms:

- Jerky shifts at very low rpm (evident in traffic jams)
- juddering at 1st / 2nd gear. The whole car will feel like it's shaking, not unlike a manual car of the 90s when you upshift too early.

Clutch replacement:

All juddering symptoms gone. Jerky shifts at very low rpm still present but less obvious.

VW by default programs the DSG clutch to upshift to 2nd gear as soon as it is able to. In traffic jam condition, the gear will shift to gear 2 very quickly, even when it is not at ideal speed conditions. This results in very quick clutch wear.

Solution: Driving the DSG in manual mode and upshifting the gears yourself will drastically slow down clutch wear, particularly during traffic jam situations. Switching back to D mode can be done once you are in moderate or clear traffic.
*
The jerks with the DSG7 of the Volkswagen are the same as the Ford's Powershift DCT, I believe. It is just that the severity of the jerks varies from car to car. Some cars have minor jerks, some cars have more severe jerks. I believe all dual-clutch transmissions in the Ford Focus (or Fiesta) exhibit this particular trait.

As for the juddering, I have sat in my friend's Jetta before and felt it briefly. It is more like vibration or shaking of the car when the car is accelerating from standstill. However, I don't feel the jerks when I sat in the Jetta. Maybe the jerks in the Jetta are very minor when the gear is upshifting. However, the juddering/vibration when accelerating from standstill (accelerating from traffic lights or junctions) is quite apparent.

I can relate to your experience in the reduced jerks during gear upshifting after the clutch replacement. I believe the jerks can be made less severe, but cannot be eliminated completely as in my mind it is an inherent character of the dual-clutch.
TSSportyHandling
post Sep 18 2015, 11:31 AM

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QUOTE(zweimmk @ Sep 18 2015, 10:29 AM)

VW by default programs the DSG clutch to upshift to 2nd gear as soon as it is able to. In traffic jam condition, the gear will shift to gear 2 very quickly, even when it is not at ideal speed conditions. This results in very quick clutch wear.

Solution: Driving the DSG in manual mode and upshifting the gears yourself will drastically slow down clutch wear, particularly during traffic jam situations. Switching back to D mode can be done once you are in moderate or clear traffic.
*
Interesting that you drive your VW in manual mode. Does your car have paddles shifters on the steering wheel?
TSSportyHandling
post Sep 18 2015, 11:44 AM

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QUOTE(dares @ Sep 18 2015, 11:26 AM)
Sounds like engine braking in low gear, with the clutch fully closed. Pros of this is the transmission downshifts responsively according to speed, that means if you want to re-accelerate it will be in the right gear. Cons is, louder engine noise and possibly jerking.

From what you described, I think the main strategy for the new TCM is to reduce clutch wear at low speeds. If you want, you can try asking SDAC to reflash the old version to your car.
*
Yes, louder engine sound and also jerking. So it's engine braking possibly to reduce clutch wear at the expense of louder engine sound and jerk? Great strategy but not so refined driving during low speed. Will see how the car performs after the clutch replacement.
TSSportyHandling
post Sep 18 2015, 11:46 AM

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QUOTE(dares @ Sep 18 2015, 10:36 AM)
The same solution suggested by some Ford Powershit owners: Drag the first gear longer using manual mode.
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WIth the Powershift transmission, I am guessing that "Manual mode" is leaving the gear in Sports mode and using the + and - buttons on the gear knob to manually change the gear?
acbc
post Sep 18 2015, 11:47 AM

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smart forfour - softtouch plus - 6 speed AMT

Jerky in AUTO mode especially crawling in heavy traffic. If in MANUAL mode, smooth. Safety mode kicks in if RPM higher than 6500 RPM.

Ever since the yaw sensor kaput, I lost both ABS and ESP and now only can drive in MANUAL mode.
dares
post Sep 18 2015, 11:49 AM

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QUOTE(SportyHandling @ Sep 18 2015, 11:44 AM)
So it's engine braking possibly to reduce clutch wear at the expense of louder engine sound and jerk?
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Well if you put it that way it people might laugh at you laugh.gif

The bottomline goal is: reduce clutch slippage. If the transmission is in the right gear at the right speed, means there is less need for half-clutching.

QUOTE(SportyHandling @ Sep 18 2015, 11:46 AM)
WIth the Powershift transmission, I am guessing that "Manual mode" is leaving the gear in Sports mode and using the + and - buttons on the gear knob to manually change the gear?
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yes. Though I suspect Powershit's manual mode is less responsive than VW's.

This post has been edited by dares: Sep 18 2015, 11:49 AM
TSSportyHandling
post Sep 18 2015, 11:51 AM

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QUOTE(zweimmk @ Sep 18 2015, 10:58 AM)
This actually is the best way to drive the car - in manual. You get to control the power and when you want the torque to come in. Depending on how you look at it also, it's either a pro or a con. I've been driving my car in almost complete manual mode after I did a clutch replacement. It just feels better that way.
*
I presume you drive the Volkswagen Passat. Does the Passat come with paddle shifters on the steering wheel, or the manual buttons are on the gear knob? I find paddle shifter(on the steering wheel) to be more useful than buttons on the gear knob when one wants to change the gears manually. Having said that, it also depends on the quality of the mechanism. I find the paddle shifting operation of the Proton Preve Turbo to be rather quirky/poor.

The Ford Focus does not come with paddle shifters. The manual controls are on the gear knob. Guess I will have to try driving manually(at low speed or heavy traffic) for few days to see how it performs.
TSSportyHandling
post Sep 18 2015, 11:57 AM

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QUOTE(Jackofree @ Sep 18 2015, 10:49 AM)
Mine is 6 speed DSG which is wet clutch but did a clutch replacement under warranty last month. My gear changes slower after clutch replacement. Asked SC why is it like that, then technician said new DSG software is programmed to change gears slower to protect the gearbox. I think this is bullshit but no choice, I guess I'll ask another SC for second opinion. Because of this, my car feels slower than usual until I floor the pedal biggrin.gif
*
I guess this is the trade-off in the tweaking or calibration of the DSG software. If the gear changes slower, you don't have the jerks which will result in a smoother or more comfortable drive, but you will have the perception that the car is lacking in power as you don't feel the speed too much. If the gear changes quicker, you feel the speed and power but at the expense of a more jerky ride, especially during light acceleration at low speed.
Boy96
post Sep 18 2015, 12:41 PM

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QUOTE(dares @ Sep 18 2015, 11:49 AM)

yes. Though I suspect Powershit's manual mode is less responsive than VW's.
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It is, after tapping that +- button it takes time for the gear to shift, summore it can only be done in S mode..

Now too lazy even in corner corner road just leave it in D..
zweimmk
post Sep 18 2015, 01:20 PM

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QUOTE(SportyHandling @ Sep 18 2015, 11:51 AM)
I presume you drive the Volkswagen Passat. Does the Passat come with paddle shifters on the steering wheel, or the manual buttons are on the gear knob? I find paddle shifter(on the steering wheel) to be more useful than buttons on the gear knob when one wants to change the gears manually. Having said that, it also depends on the quality of the mechanism. I find the paddle shifting operation of the Proton Preve Turbo to be rather quirky/poor.

The Ford Focus does not come with paddle shifters. The manual controls are on the gear knob. Guess I will have to try driving manually(at low speed or heavy traffic) for few days to see how it performs.
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I can use both the paddle shifters or the traditional gearstick into manual mode (push up to shift up and down to shift down). The response and gear change is always immediate either way.

Basically I only need to shift up, the gearbox will shift down automatically for you or you can do it yourself if you feel like it or need to do any engine braking.

All these wear and tear are caused by excessive half-clutching in low speed and traffic jams. I guess they didn't account on how much wear and tear our cars have to endure because of traffic conditions. The current solution they have won't resolve the clutch wear issue. The only effective method is to manually shift the gears yourself in traffic jams.

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