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Zombie Thread, back from the dead after 4+ years.
Interestingly my, or my daughters I should say, Focus is very smooth when cold but can get a case of the shudders when the engine and trans are hot, but not all the time and only on pick up in first gear. I googled to see if I could find anything as to exactly what could cause this but closest I can see is fluid contamination of the clutch faces which I'm thinking isn't what is happening in my case as it's smooth when cold. Masses of hits like 'it does it', it's crap, what's going on?, I should never have bought it etc etc but nothing as to what is happening to cause this issue. Surely Ford and the transmission supplier must be able to figure why it happens. I'm curious as to what is causing this issue so any links appreciated. If it isn't fluid or other clutch contamination, and the driving conditions are the same for cold engine, hot engine why does it occasionally shudder when the engine is hot? why? maybe it's an early sign of clutch demise? It has 17K miles on it.
 

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One of the key issues in the development of a dry dual clutch (DCT) is clutch durability. In dry clutches with current linings, above a critical temperature, the friction system starts to suffer permanent damage. In addition, the clutch friction characteristics are a function of the clutch interface temperature. Because a reliable, low-cost temperature sensor is not available for this application, the clutch control engineers rely on a good thermal model to estimate the temperature of the clutches.

Conventional vehicle transmissions predominantly employ wet clutches to accomplish gear shifting. Transmissions typically include a transmission fluid which is recycled throughout the transmission. Wet clutches generally provide greater heat transfer and temperature control than dry-clutches. Wet clutches also, however, have a lower coefficient of friction than dry-clutches.

Dry-clutches tend to provide higher coefficients of friction than wet clutches. Dry-clutches can provide lower costs and complexity. Still, dry-clutches have thermal management issues. For example, dry-clutches can reach higher temperatures in repeat vehicle launch events (stop & go traffic conditions) with heavy vehicle load and road grade conditions.

My simple theory is is that with the thermal (heat) issues, this heat is causing premature breakdown of the seals that are supposed to keep the oil from contaminating the clutches. This heat begins to create havoc with the Transmission Control Module which is working very hard at maintaining a proper shifting transmission, but over time with the seals breaking down, clutches are heavily contaminated, which creates the terrible shuddering.

Also it is my assumption that even with new clutches & seals etc, the TCM (Transmission Control Module) is the next weakest link as it is being put under very high stresses dealing with the thermal issues and trying to keep some sort of decent shift action. Hence replacement of the TCM as well.

Good that Ford put the extended warranty coverage on the clutch and TCM , but I think the next bits that should have this extended warranty coverage are the electric motors or shift actuators that are next in line to break down.
 

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Nope

Sent from my SM-N900P using Tapatalk
 

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One of the key issues in the development of a dry dual clutch (DCT) is clutch durability. In dry clutches with current linings, above a critical temperature, the friction system starts to suffer permanent damage. In addition, the clutch friction characteristics are a function of the clutch interface temperature. Because a reliable, low-cost temperature sensor is not available for this application, the clutch control engineers rely on a good thermal model to estimate the temperature of the clutches.

Conventional vehicle transmissions predominantly employ wet clutches to accomplish gear shifting. Transmissions typically include a transmission fluid which is recycled throughout the transmission. Wet clutches generally provide greater heat transfer and temperature control than dry-clutches. Wet clutches also, however, have a lower coefficient of friction than dry-clutches.

Dry-clutches tend to provide higher coefficients of friction than wet clutches. Dry-clutches can provide lower costs and complexity. Still, dry-clutches have thermal management issues. For example, dry-clutches can reach higher temperatures in repeat vehicle launch events (stop & go traffic conditions) with heavy vehicle load and road grade conditions.

My simple theory is is that with the thermal (heat) issues, this heat is causing premature breakdown of the seals that are supposed to keep the oil from contaminating the clutches. This heat begins to create havoc with the Transmission Control Module which is working very hard at maintaining a proper shifting transmission, but over time with the seals breaking down, clutches are heavily contaminated, which creates the terrible shuddering.

Also it is my assumption that even with new clutches & seals etc, the TCM (Transmission Control Module) is the next weakest link as it is being put under very high stresses dealing with the thermal issues and trying to keep some sort of decent shift action. Hence replacement of the TCM as well.

Good that Ford put the extended warranty coverage on the clutch and TCM , but I think the next bits that should have this extended warranty coverage are the electric motors or shift actuators that are next in line to break down.
I'm assuming also that a conventional manual transmission is a dry clutch set up in that the only 'fluid' is the gearbox oil and the clutch face is dry unless the seals leak. I'm thinking in my case at least there isn't any foreign contamination of the clutch faces as I would expect the kangaroo hops to be present all the time whether hot or cold. These clutch faces are I assume very small when compared to a standard manual trans?
It's a shame because I think it's a great car in terms of kerb appeal and features.
 

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Moving this to the MkIII Problems section to join the other threads of it's type. You can find most of the transmission info. in that section.

The pair of dry clutches used in this transmission are stacked in line with each other, not two rings on the same plane, so they have the space to be of similar size to a single manual trans. clutch even though operated differently by stepper motor actuators and linkages.

As GhiaFan mentioned, heat from repeated slipping of the clutches is the main issue with dry clutches. Original design from Getrag (some links to articles here, or google) included using "shudder" intentionally as a warning of excess heat building to "train" users to avoid/minimize circumstances where that tends to happen. Supposedly that was not included in the final design, leaving the warnings to the worst case overheating light warning & limp mode only.

This was the reason behind the "How to Drive" thread started by one member that got "stickied" at the top of the MkIII section.

Repeated or extended operation below 5 MPH is the range where the clutch has to slip repeatedly heating it up, no matter what programming is used to engage/disengage the clutch to mitigate this. This is like using a manual transmission without ever letting it fully engage in gear.

In most "normal" driving this isn't an issue, though there are always exceptions. For the extreme example we've all seen drivers holding a car at a stop on a hill using the transmission rather than the brake, warned against with std. torque converter types as well due to rapid heat build up.

One other piece of advice for good results you'll see here regularly is to drive it hard regularly or "scrub the clutches" with a couple hard 0-60 runs on occasion. This comes from the manual trans world, where clutch "chatter" from prev. hard use can be reduced/eliminated with repeated smooth engagement of the clutch under power.

Despite new seals that have virtually eliminated seal leakage issues as a regular issue and improved clutch materials/design, the number of variables in manufacture & use can still conspire to cause issues with shudder. TCM problems with computer electronics failure or shift actuator problems cause different problems, clutch actuator & linkage problems mentioned earlier can also affect the shudder/shifting issues as a cause.

Some say the "driving instructions" should not be necessary. All I can say is that they exist for everything, some being more sensitive than others to how they're used. Got 'em at home, from books and from Driver's Ed on operating a std. torque converter type when learning to drive myself with a separate set for manual transmissions. Even then (60's to 70's) there were a couple typical automatics and a few typical manuals to learn, plus oddballs like automated stick shift you might never actually use yourself. (That one was actually kinda fun when I finally had one for a short time)
 

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How is yours driving now you have had the clutches replaced. Any bucking at all? or all smooth?
SMOOTHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH and perfect. Almost feels like a CVT 1speed tranmission at times. If ford could get this to stay for the life of the vehicle they could've hit a homerun.

Right now its one of the smoothest cars i drove in. It might jerk slighty if i do a "roll stop", but nothing like before where it would jerk like a new stick driver.
 

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I'm assuming also that a conventional manual transmission is a dry clutch set up in that the only 'fluid' is the gearbox oil and the clutch face is dry unless the seals leak. I'm thinking in my case at least there isn't any foreign contamination of the clutch faces as I would expect the kangaroo hops to be present all the time whether hot or cold. These clutch faces are I assume very small when compared to a standard manual trans?
It's a shame because I think it's a great car in terms of kerb appeal and features.
Some Powershift (6DCT250 dual dry clutch) info for your reading pleasure
Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview - Team-BHP

And the video at the end of the DCT thread is worth watching. https://www.youtube.com/watch?v=6iCRnAUftvI
 

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SMOOTHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH and perfect. Almost feels like a CVT 1speed tranmission at times. If ford could get this to stay for the life of the vehicle they could've hit a homerun.

Right now its one of the smoothest cars i drove in. It might jerk slighty if i do a "roll stop", but nothing like before where it would jerk like a new stick driver.
OK, do we have on this site a drivers log where folks who have had early transmission work can log the pre/post work details and update the log as and when required. I can't recall your mileage but I think it was low, so I'm thinking either:
You and other drivers had component failures that once identified by Ford engineers will be fixed and you'll be a happy customer from here to the 'end of the road' so to speak, or,
You've beaten the crap out of the vehicle and destroyed something that would ordinarily wouldn't fail and that takes some doing in modern cars. They will put up with way more abuse than say something from the 70's....or..
There is an inherent design problem, in which case heaven help us all.
Can you keep us updated as time goes on if you start to get a case of the twitches or shudders?
Thanks
 

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Some Powershift (6DCT250 dual dry clutch) info for your reading pleasure
Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview - Team-BHP

And the video at the end of the DCT thread is worth watching. https://www.youtube.com/watch?v=6iCRnAUftvI
Thanks, I'll take a look, it's certainly a most intriguing piece of kit. Thanks also to Sailor for the taking the time to respond to previous post. Well, I'm very perplexed as to why I get intermittent collywobbles when hot and it isn't after stop go city driving either. With that said it would be 30 mph suburbs. Unfortunately I don't drive it enough, my job is to refuel it every Sunday and I've been well impressed with it's lack of 'wobble' when cold, I thought that the adaptive learning had kicked in with my daughters very careful driving and all was good. It was only when I had to move it the other day when it was hot and I got the wobbles when moving off. I've asked her to try and log when the wobbles occur. Very peculiar how this scenario occurs when it's hot and not all the time. It's almost like the transmission mounts are loose, that's the best way I could describe it. Thanks guys I appreciate you taking the time to respond. I'm considering contacting Ed China.
 

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Overall heat can cause the shudders when they otherwise don't show. Doesn't have to be from driving in traffic etc..

This has been reported in cases such as after a long drive on the interstate (hot weather) and shows for a short time afterwards. How soon it goes away then depends on temps. & driving.

If there was a single simple fix this would have ended entirely long ago.

For shudder alone seals, clutches & tuning come into play. Ford keeps tweaking the tuning, but they have multiple objectives in mind and have to create a one size fits all solution. A Vendor here (Tuner) is offering a deal on tuning to reduce shudder, he's had about 98% success so far with eliminating the problem. Custom adjustments included can help beyond the std. tuning he does for the transmission, it started for engine/trans. performance but the benefits ended up being more widespread.
 

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I read these posts....WHY DOES'NT FORD WARRANT EVERYTHING TO WITH THE TRANS-FOR 10 YEARS 150k MILES LIKE IT DOES THE TCM? WHY ONLY THE TCM & CLUTCHES 7/100K/?? WHAT GIVES HERE?? PLEASE EXPLAIN SOMEBODY!!
 

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You've been around through all of it to see the history, each of those extensions were made at different times for different reasons.

The first (clutches/seals/programming) made at a time when the latest fix was expected to solve the shudder issues for the vast majority, and was then stock on the latest production. Extension made to cover anyone up to that point with the latest setup when/if needed.

The second (TCM) came about later when they determined that too many wouldn't reach 10/150k without a failure. Only came about after more cars had higher mileage and showed the issue.

Anyone can speculate on why no changes since then, but we're working without any statistics they'd be using for decisions (whatever we might think would be nice to see).
 

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I read these posts....WHY DOES'NT FORD WARRANT EVERYTHING TO WITH THE TRANS-FOR 10 YEARS 150k MILES LIKE IT DOES THE TCM? WHY ONLY THE TCM & CLUTCHES 7/100K/?? WHAT GIVES HERE?? PLEASE EXPLAIN SOMEBODY!!
Because someone at Ford has done the math and concluded that they'd come out ahead financially the way they are doing it.

Such calculations always involve making some assumptions about things they cannot know for certain, like what effect various decisions will have on future sales. I think that is one area where they have miscalculated with this problem.
 

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I read these posts....WHY DOES'NT FORD WARRANT EVERYTHING TO WITH THE TRANS-FOR 10 YEARS 150k MILES LIKE IT DOES THE TCM? WHY ONLY THE TCM & CLUTCHES 7/100K/?? WHAT GIVES HERE?? PLEASE EXPLAIN SOMEBODY!!
because bumper to bumper is 3-36, powertrain is 5-60, the reason its extended only for those is because they found those are the things that fail. if you want a longer warranty shouldve got an ESP. You shouldnt have an issue if you take care of your car, and ford has decided to cover the problem areas that can fail regardless of maintenance.
 
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