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My manual transmission makes a rattle noise almost sounds like a helicopter only does this with foot off the clutch just sitting if you push the clutch down it stops. It's 2014 and has 8000 miles. Do you all have this issue to?
 

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Rebecca
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negative. Maybe something is loose in there.
 

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My manual transmission makes a rattle noise almost sounds like a helicopter only does this with foot off the clutch just sitting if you push the clutch down it stops. It's 2014 and has 8000 miles. Do you all have this issue to?
That is called gear lash rattle or rollover rattle. Totally normal for the MTX-75 manual tranny. When the gear is in neutral and the clutch is not depressed, it rattles. When you depress the clutch, it stops. It gets louder when the engine is fully warmed up and the ambient temperature is high.
 

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Discussion Starter #4
We have had other focuses with sticks come in where I work and none of them have sounded like mine though.
 

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Focus Preacher
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My manual transmission makes a rattle noise almost sounds like a helicopter only does this with foot off the clutch just sitting if you push the clutch down it stops. It's 2014 and has 8000 miles. Do you all have this issue to?
That is called gear lash rattle or rollover rattle. Totally normal for the MTX-75 manual tranny. When the gear is in neutral and the clutch is not depressed, it rattles. When you depress the clutch, it stops. It gets louder when the engine is fully warmed up and the ambient temperature is high.

Affirmative... its worse when she's hot!!
 

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The noise may be the 'dual mass' flywheel springs.
The can break, or get weak....
Then they would be rattling like crazy in neutral, as they would be then free to rattle like crazy....
When moving in gear they would be less prone to be rattling....
This is my opinion.
 

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Focus Preacher
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The noise may be the 'dual mass' flywheel springs.
The can break, or get weak....
Then they would be rattling like crazy in neutral, as they would be then free to rattle like crazy....
When moving in gear they would be less prone to be rattling....
This is my opinion.
It's 2014 and has 8000 miles
Very very unlikely but slight chance of possibility...

Also he would experience some serious off balance issues (vibration) with the "broken" dual mass flywheel

Further on a bad dmf , starter will start to grind/slip but then damage to the tranny is imminent!!
 

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If I wanted to drain the fluid and put some other stuff in there what would I use?
Well the OEM fluid is very good. And very expensive.
Optional fluids are synthetic, Mobil One, Royal Purple, Maybe one other...
The thing is the fluid in the transmission is about as good as it can get. [like]
 

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That is called gear lash rattle or rollover rattle. Totally normal for the MTX-75 manual tranny. When the gear is in neutral and the clutch is not depressed, it rattles. When you depress the clutch, it stops. It gets louder when the engine is fully warmed up and the ambient temperature is high.
When you say it is normal, are you saying that all MTX75 manual transmissions have this and it is just the design?

I just picked up a '12 Focus SE with manual transmission a few weeks ago and haven't noticed any odd sounds, but it is has been at or below freezing since that time.

If the sound is there is there anything that can be done? Would a manual transmission fluid change help for this issue?
 

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Definitely not normal, None of the manual focus' I have driven nor my own do it. There is a little clutch release bearing noise when the clutch is down, but silent when up. No vibration or rattle at all

Does it change frequency with engine revs?
 

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When you say it is normal, are you saying that all MTX75 manual transmissions have this and it is just the design?

I just picked up a '12 Focus SE with manual transmission a few weeks ago and haven't noticed any odd sounds, but it is has been at or below freezing since that time.

If the sound is there is there anything that can be done? Would a manual transmission fluid change help for this issue?
You may not hear the rattle when the ambient temperature is below freezing. And remember it will only rattle when the clutch is up and the stick is in neutral. The gear rattle becomes noticeable when the car is fully warmed up and the outside temperature is high. Here is what causes gear lash rattle:

A piston engine's power delivery is not seamless like an electric motor. A piston engine makes pulses of power very rapidly. How often? In the M3, (3 X rpm) per minute. Now realize that any drivetrain component (transmission or differential) has a certain amount of looseness or slack in it - it must, or being too tight would create a lot more friction. So when the power pulse engages the transmission, it is causing the rotational power going through the unit to take up that slack. This effectively causes components to touch that were not pressed together a moment before. Between each power pulse, those components de-couple. Press any two hard objects together, whether it be a tea cup and saucer or a hammer and nail, and you notice that noise is made. Repeat the contact-release-contact cycle quickly and it makes a staccato sound - a rattle.

http://www.nexternal.com/uuc/articles/gear_rattle.htm
 

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Except of course there should be oil between those components preventing contact, noise and vibration.
Also at idle say 700 rpm, that would be a frequency of 35Hz, which is below human hearing range, but too frequent by far to be a "rattle".

Would suggest a rattle needs investigating, at the frequency mentioned more likely something purely to do with the rotation of the clutch and therefore more likely debris in clutch housing or a feature of the 2 part clutch (although I've been driving a 2 part clutch for the last 15 years and it was silent)
 

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Except of course there should be oil between those components preventing contact, noise and vibration.
Also at idle say 700 rpm, that would be a frequency of 35Hz, which is below human hearing range, but too frequent by far to be a "rattle".

Would suggest a rattle needs investigating, at the frequency mentioned more likely something purely to do with the rotation of the clutch and therefore more likely debris in clutch housing or a feature of the 2 part clutch (although I've been driving a 2 part clutch for the last 15 years and it was silent)
I don't think you have the MTX75 tranny on your diesel focus....

Please double check that.
 

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Except of course there should be oil between those components preventing contact, noise and vibration.
Also at idle say 700 rpm, that would be a frequency of 35Hz, which is below human hearing range, but too frequent by far to be a "rattle".

Would suggest a rattle needs investigating, at the frequency mentioned more likely something purely to do with the rotation of the clutch and therefore more likely debris in clutch housing or a feature of the 2 part clutch (although I've been driving a 2 part clutch for the last 15 years and it was silent)
Gear lash rattle is not unique to the MTX-75. BMW and others also have this.

"I am a tech at BMW and have heard this complaint numerous times from customers with zhp. The BMW rep and myself came to the conclusion that this is a normal noise caused by the lightened flywheel..."

http://www.bimmerforums.com/forum/showthread.php?1318681-Light-rattle-when-in-neutral-ZHP
 

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My manual transmission makes a rattle noise almost sounds like a helicopter only does this with foot off the clutch just sitting if you push the clutch down it stops. It's 2014 and has 8000 miles. Do you all have this issue to?
Have you spoken with your service manager about this? Once you do, please send me a private message with your VIN, updated mileage, best daytime phone, full name, and dealer name/location. I'll check into some additional assistance.

Meagan
 

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52k miles on mine, I don't have any such rattle. On the other hand, both my old bimmers (like, a LOT older bimmers...) have a little rattle, funny someone should mention that.
 

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I only have 2000 miles on mine, but no rattles yet...
 

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I may have heard this noise, a couple of times, last July after driving for several hours at highway speeds. I pulled off into a truck stop to gas up, with the window about two inches open, maybe the gas pump reflected some of the sound before I shut off the motor.

When I gassed up, used the restroom, and took off again, no more noise. Nothing since.
 
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