Does anyone know what makes that grinding noise on the DCT

[xpartmgr]

I know I will likely get flamed for another DCT thread, but I am curious if anyone knows what the noise actually is? I mean Ford says it is normal, many of us have it and it seems totally not normal to us. I was just wondering if Ford has said what or why it makes that noise when it shifts from 1st to 2nd? Why only when it goes from an odd to an even gear? mine does it from 1st to 2nd and from 3rd to 4th, but never from 2nd to 3rd. So I am curious if anyone actually knows what part is making the noise and why it is only some cars but not others? Why only from odd to even gears?

Perhaps this is someplace else, but with all these DCT threads I can't find it! That was a joke.

[Sponsor]

[InfinityCubed]

One person has had their clutches replaced, with 300 miles on the new clutches so far and no grinding sound, found here: http://www.focusfanatics.com/forum/s...286870&page=12 post #554 (I have mine set on 50 posts per page so that may not show you the right page but it is post 554)

And one getting clutches replaced now is here: http://www.focusfanatics.com/forum/s...=297294&page=2 Post #54

[YesMAN]

This blurb is in the "Operating Characteristics" pamphlet that's been circulated on the forum.

Low speed grinding. A slight grinding noise may be heard at about 2 MPH. This noise is more evident during “trailer-hitching” events (see below). This noise is caused by a normal bearing rotation and does not affect the durability of the transmission.

[xpartmgr]

Originally Posted by YesMAN

This blurb is in the "Operating Characteristics" pamphlet that's been circulated on the forum.

Low speed grinding. A slight grinding noise may be heard at about 2 MPH. This noise is more evident during “trailer-hitching” events (see below). This noise is caused by a normal bearing rotation and does not affect the durability of the transmission.

I have seen this, but I am talking about way more than 2 mpg and no trailer hitching. I can put it in 2nd gear and slow down, when I accelerate it will grind for 3-7 seconds! This sounds like the noise, but the speed and conditions are not the same. I am one of many with this issue.

[DayGlow]

I think the techno-speak is that 'normal' means that they have determined that it doesn't effect the longevity of the transmission and falls into whatever operational tolerances that they can defend in court if need be... I doubt the grinding is 'optimal' for the transmission

[2012sel]

Originally Posted by xpartmgr

I know I will likely get flamed for another DCT thread, but I am curious if anyone knows what the noise actually is? I mean Ford says it is normal, many of us have it and it seems totally not normal to us. I was just wondering if Ford has said what or why it makes that noise when it shifts from 1st to 2nd? Why only when it goes from an odd to an even gear? mine does it from 1st to 2nd and from 3rd to 4th, but never from 2nd to 3rd. So I am curious if anyone actually knows what part is making the noise and why it is only some cars but not others? Why only from odd to even gears?

Perhaps this is someplace else, but with all these DCT threads I can't find it! That was a joke.

This may be a different symptom as I would describe my situation as more of a vibrating shudder in the odd to even gear shifts. Especially at speeds from 5mph to 30mph when the engine seems to be bogging down a bit. This started on my car at about 12,000 miles.

I've had plenty of manual transmission cars and know that clutches can get a surface condition that makes the slip characteristics worsen. In other words if the clutch is understressed or overstressed, the clutch friction gets greater and what should be very brief slippage on engagement become very abrupt and heavy vibration occurs. This happens on my '57 Chevy pickup when the clutch is cold and I have to be more careful the first few miles. Or if I've driven on the highway a while and the clutch cooled down.

What I did on my Focus that seems to have eliminated or lessened the shuddering...
Using sport mode, I made the shift from an odd gear to an even gear (1st to 2nd, 3rd to 4th, 5th to 6th) be under heavy load. I floored the accelerator while in an odd number gear and then shifted gears to the even number gear at as high of RPM as I could get it to do. I did this about 9 times (three times in all three odd to even gear change) and the problem has gone away. So Far, but I only have about 1000 miles since doing it.

[xpartmgr]

Originally Posted by 2012sel

This may be a different symptom as I would describe my situation as more of a vibrating shudder in the odd to even gear shifts. Especially at speeds from 5mph to 30mph when the engine seems to be bogging down a bit. This started on my car at about 12,000 miles.

I've had plenty of manual transmission cars and know that clutches can get a surface condition that makes the slip characteristics worsen. In other words if the clutch is understressed or overstressed, the clutch friction gets greater and what should be very brief slippage on engagement become very abrupt and heavy vibration occurs. This happens on my '57 Chevy pickup when the clutch is cold and I have to be more careful the first few miles. Or if I've driven on the highway a while and the clutch cooled down.

What I did on my Focus that seems to have eliminated or lessened the shuddering...
Using sport mode, I made the shift from an odd gear to an even gear (1st to 2nd, 3rd to 4th, 5th to 6th) be under heavy load. I floored the accelerator while in an odd number gear and then shifted gears to the even number gear at as high of RPM as I could get it to do. I did this about 9 times (three times in all three odd to even gear change) and the problem has gone away. So Far, but I only have about 1000 miles since doing it.

I have tried some 'hard" shifting but to no avail. I was just curious as to what is making the noise. I mean if they say it is normal they must know what is causing it right??? So perhaps an explanation of the what and why would help people understand their point of view. Just hiding behind "normal operation" is not an explanation. I guess I expect more than I will ever get.

[hotleadsingerguy]

The noise is simply the transition from one clutch to the other. In the case of most people, it's the transition from clutch #1 to clutch #2 (so 1-2, 3-4, and 5-6). There's no way of "fixing" it, aside from replacing the clutches. Most likely it's a problem with either the first clutch disengaging or the second clutch engaging. It would most likely do the same thing downshifting into an even gear from an odd one under load, although slightly less pronounced).

The actual reason is most likely close to what they said: It's probably a bearing in one of the clutch systems that just makes noise. No real thing to worry about, but it would affect the overall life of the clutch (we're talking like 95,000 miles instead of 100,000).

[xpartmgr]

Originally Posted by hotleadsingerguy

The noise is simply the transition from one clutch to the other. In the case of most people, it's the transition from clutch #1 to clutch #2 (so 1-2, 3-4, and 5-6). There's no way of "fixing" it, aside from replacing the clutches. Most likely it's a problem with either the first clutch disengaging or the second clutch engaging. It would most likely do the same thing downshifting into an even gear from an odd one under load, although slightly less pronounced).

The actual reason is most likely close to what they said: It's probably a bearing in one of the clutch systems that just makes noise. No real thing to worry about, but it would affect the overall life of the clutch (we're talking like 95,000 miles instead of 100,000).

Perhaps this is correct. However what it affects is the resale value. Would you buy a car if you drove it and it made that noise? What if I told you don't worry Ford said it is normal? Would that change your mind and you give me full price? I am not being mean, just asking a question. I agree that it is likely in the clutch assembly, but I am really curious to the real reason. I just want Ford to go on record and say "hey that noise is normal, it is the xyz and when it does something it can make a noise". I do not think asking for a real explanation is too much to ask for.

[PratoN]

I'll just leave this right here:

http://www.focusfanatics.com/forum/s...9&postcount=81

(My car this past Saturday)

As far as I can tell, it doesn't help with the jerkiness of the transmission and frankly it's just embarrassing. Luckily I listen to music 24/7, but for someone that does not - you'll definitely hear this.