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Weird transmission sounds, finally caught on film

TyphoonFiST

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#42
I was creepin on your profile and saw you had your trans replaced for being under-filled - what were the symptoms that lead to your trans replacement?
It was a mad bearing howl that started in 4th gear and eventually went into 5th and then 6th gear. The exact failure was never pin pointed due to no Tear down being authorized by ford and Just a full on replacement installed instead. As soon as I got it home....I drained the Transmission and put in 2L/ 2Qts. Of Ravenol 75w80 MTF-2. Been a happy camper ever since doing so.

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Clint Beastwood

Clint Beastwood

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Thread Starter #43
It was a mad bearing howl that started in 4th gear and eventually went into 5th and then 6th gear. The exact failure was never pin pointed due to no Tear down being authorized by ford and Just a full on replacement installed instead. As soon as I got it home....I drained the Transmission and put in 2L/ 2Qts. Of Ravenol 75w80 MTF-2. Been a happy camper ever since doing so.

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Did you have to work at getting it replaced, or once they replicated the issue it was pretty much a "yeah its f*cked" situation?
I don't think they actually needed to replace my axles, things *did* quiet down significantly after they swapped them for a while, but then overnight it pissed out what looked like a quart of trans oil onto my driveway and had to have new seals installed after 24 hours. I have no way of knowing if it was under-filled before that, but it was *definitely* low when I drove it back to the dealership. Since the axle swap its just been getting louder and louder.

My whine/hum seems to be in 3rd and 4th gears. If you are driving on flat ground and let off throttle/on throttle/off throttle/on throttle the "slapping" from the trans is extremely audible, and its the same "quality" of sound as the whirring/grinding I get when coming to a stop. The whirring/grinding is starting to be present when I am coasting on flat ground, but it still most audible when you are decelerating, take the car out of gear, let off the clutch and brake somewhat hard. The sounds always there, but it's loudest then. I can't find a TSB for the trans being underfilled, but if they're going out almost half underfilled thats a big problem and topping off the fluid just offloads the issue onto the purchaser.
 


TyphoonFiST

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#44
Did you have to work at getting it replaced, or once they replicated the issue it was pretty much a "yeah its f*cked" situation?
Took the Tech on a test drive....everything turned off stereo....HVAC Etc. Was like a 2 min test drive....Tech was like... Yeap definitely an issue going on. Sent a Ford Rep. Out the next Day to decide if it was a Teardown or Remove and Replace with A new Unit. Ford Deemed it non Teardown and then installed a new unit. So maybe 3 days before I had the Vehicle back in my possession.

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Clint Beastwood

Clint Beastwood

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Thread Starter #45
Took the Tech on a test drive....everything turned off stereo....HVAC Etc. Was like a 2 min test drive....Tech was like... Yeap definitely an issue going on. Sent a Ford Rep. Out the next Day to decide if it was a Teardown or Remove and Replace with A new Unit. Ford Deemed it non Teardown and then installed a new unit. So maybe 3 days before I had the Vehicle back in my possession.

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Ok rad. I'm a pretty patient dude, but when it comes down to demonstrating a sound for someone its almost always a pain in the ass until the sound is ridiculously audible.
 


FiSTerMr

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#46
It was a mad bearing howl that started in 4th gear and eventually went into 5th and then 6th gear. The exact failure was never pin pointed due to no Tear down being authorized by ford and Just a full on replacement installed instead. As soon as I got it home....I drained the Transmission and put in 2L/ 2Qts. Of Ravenol 75w80 MTF-2. Been a happy camper ever since doing so.

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How many miles do you have on the Ravenol?

2017 w/Recaros - bone stock
 


MagnetiseST

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#47
Gonna do an LSD while it's down and out?

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Nope. It needs a whole transmission...


Update:

pulled the transmission and opened it up. Input shaft had an unusual amount of play in it. Unbolted the gearsets, attempted to remove them, and the input shaft fell out.

Turns out the input shaft broke between gears 2 & 3. Cracked clean in half. There was NO metal in the transmission fluid. I was so sure it was a bearing.

Oh well. New transmission on the way.
 


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#50
Nope. It needs a whole transmission...


Update:

pulled the transmission and opened it up. Input shaft had an unusual amount of play in it. Unbolted the gearsets, attempted to remove them, and the input shaft fell out.

Turns out the input shaft broke between gears 2 & 3. Cracked clean in half. There was NO metal in the transmission fluid. I was so sure it was a bearing.

Oh well. New transmission on the way.
That is a damn near perfect clean break, which makes me wonder as to the condition that caused it to break. Torsional break would be a severe turning in the shaft from extreme torque so that’s not it. Not sheared either as if it was shock loaded. Interesting to see, and glad you got it diagnosed.


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#51
That is a damn near perfect clean break, which makes me wonder as to the condition that caused it to break. Torsional break would be a severe turning in the shaft from extreme torque so that’s not it. Not sheared either as if it was shock loaded. Interesting to see, and glad you got it diagnosed.
I’m curious as well…what is the cause? I’m guessing it’s correlated with the “clank”. I noticed there appears to be a lot of back lash in the transmission. Someone mentioned it could be play in the differential.

The clean break appears to have been where a machined groove is on the shaft. Is that correct?
 


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MagnetiseST

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#52
That is a damn near perfect clean break, which makes me wonder as to the condition that caused it to break. Torsional break would be a severe turning in the shaft from extreme torque so that’s not it. Not sheared either as if it was shock loaded. Interesting to see, and glad you got it diagnosed.


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So my fabricator friend seems to think it was a flaw in the original forging process. There may have been an air bubble in the metal and it never released (hence the dimpled shiny part), then being driven really hard just exacerbated it. The car is driven daily (hard) and driven on the track, it has been drag racing exactly twice. So I'm not sure how much sense it makes to be from shock, but it could be.
 


FiSTerMr

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#53
...I noticed there appears to be a lot of back lash in the transmission. Someone mentioned it could be play in the differential.
I definitely think that is what's going on. Backlash.



2017 w/Recaros - bone stock
 


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Clint Beastwood

Clint Beastwood

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Thread Starter #54
I definitely think that is what's going on. Backlash.



2017 w/Recaros - bone stock
Thats how it feels. There's so much "slop" inside the transmission.

Let off gas, split second later "thunk" as the slop is taken up, back on gas, split second later" thunk" as the slop is taken up in the other direction.

It's not the same sort of slop as before the cobb RMM, it feels like its inside the trans, like i can feel it through the shifter and clutch pedal.
 


FiSTerMr

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#55
Thats how it feels. There's so much "slop" inside the transmission.

Let off gas, split second later "thunk" as the slop is taken up, back on gas, split second later" thunk" as the slop is taken up in the other direction.
Mine had that backlash-like click/clunk since I bought it with 2,500mi. The previous owner mentioned how tricky the car was shifting in lower gears, so perhaps he fucked it up in the time he had it, idk.
The weird thing is, is that it sounds exactly the same as when you change gears when the clutch is depressed; which I know is the linkage noise and harmless.

And if the clutch is depressed, there's no way the noise is backlash... Nontheless, there is natural backlash in these transmissions, as with any gear box. The question remains, is it excessive? [emoji1745]

2017 w/Recaros - bone stock
 


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#56
So my fabricator friend seems to think it was a flaw in the original forging process. There may have been an air bubble in the metal and it never released (hence the dimpled shiny part), then being driven really hard just exacerbated it. The car is driven daily (hard) and driven on the track, it has been drag racing exactly twice. So I'm not sure how much sense it makes to be from shock, but it could be.
You’re fabricator friend seems right to me. A shock loaded break would’ve caused a much more violent and non uniformed tear in my opinion. Not to mention shock loaded failures tend to destroy everything around it (which I’m assuming didn’t happen from your pic).


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#57
Thats how it feels. There's so much "slop" inside the transmission.

Let off gas, split second later "thunk" as the slop is taken up, back on gas, split second later" thunk" as the slop is taken up in the other direction.

It's not the same sort of slop as before the cobb RMM, it feels like its inside the trans, like i can feel it through the shifter and clutch pedal.
Do you have side mounts or inserts? Or is it just the Cobb rmm? I had the same issues with shifting until I put powerflex inserts in and trans bracket shifter bushings.


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#58
You’re fabricator friend seems right to me. A shock loaded break would’ve caused a much more violent and non uniformed tear in my opinion. Not to mention shock loaded failures tend to destroy everything around it (which I’m assuming didn’t happen from your pic).


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If the break happened inline with a machined groove on the O.D. would cause a clean break as shown in the picture.
 


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Clint Beastwood

Clint Beastwood

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Thread Starter #60
They’re saying it’s my brake rotors. Despite the issue existing before and after replacing the pads and rotors in the last 5k miles. :facepalm:

When I demonstrated the driveline “slapping” he made a weird face then blanked back up and said it might be normal.

I do not enjoy the mushroom treatment.
 




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