Clutch Recall (FCA W12 | 20V-124) on 2018-2020 JL Manuals [overheating clutch pressure plate]

sf5211

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Ok, I broke out the Sherlock Holmes magnifying glass and found the thread..
Sorry I’m electronically limited and don’t know how to post the thread but it’s called..
“Fire result of transmission failure”
His forum name is DuramaxJack3D (nice guy 1st name Jay)
In his post #11 he states 3rd gear, normal driving slight hill.





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DanW

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Technically it spins at engine rpm. Force is the same revved up in neutral as it would be at 100 mph in 3rd or 4th
Sorry for any confusion. I'm no physicist or engineer, but I'm pretty sure centrifugal force is greater at 3500rpm than at 1500. I asked about rpm, not speed. The only reason I mentioned highwasy speed is because typicaly your engine rpm is at 2000 to 2500 for extended periods, giving the force more time to pull things apart if the plate is fractured. But 3500 going up a hill sustains the high level of force for longer than one typically operates there. If I'm at or above 3500, it is usually only for a very short time. But I am there or passing through 3500 on the way to redline very frequently.

Either way, once the plate is heat damaged and fractured, it could probably come apart at any time, under any driving condition, whether sitting at idle or running up to redline momentarily, or cruising at 2300rpm. I would only imagine it to be more severe in terms of exiting the bell housing if moving a little faster. But idle might still be enough. I really have no clue. But that's why I was curious about it.
 

DanW

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No Dan, he claimed he was driving normally.
What I find interesting is I just searched the forum and can’t find that thread. Hmm,
I remember it was Ocean Blue but I wish I could remember the person.
I also tried to go back on my history and the only thing I found was the first clutch recall thread which was after that guys fire.
I think they probably bought his Jeep back and part of the terms could have been to cease and desist talking about it, But maybe not, since the insurance company would have been the one to get paid for the Jeep.


But that's speculation about speculation. Lol!

But they won't go back and tell him what they found in their investigation. He'll probably have to learn about it from the same sources we have, which are basically only the NHTSA and FCA.

But I do have my friend who is checking with his former colleagues at Stalantis/FCA to see if he can get any additional info, mainly on the fix, but also on the problem. Stay tuned for that. Not sure when he'll get the chance and then get the chance to get back with me.
 

DanW

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Ok, I broke out the Sherlock Holmes magnifying glass and found the thread..
Sorry I’m electronically limited and don’t know how to post the thread but it’s called..
“Fire result of transmission failure”
His forum name is DuramaxJack3D (nice guy 1st name Jay)
In his post #11 he states 3rd gear, normal driving slight hill.
So I'd guess anywhere from 2200 down to 1500 rpms. Again, probably no conclusions can really be drawn from that, but it still satisfies some curiosity. It does seem that the damage to the pressure plate was already done before it came apart.
 

Toycrusher

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Sorry for any confusion. I'm no physicist or engineer, but I'm pretty sure centrifugal force is greater at 3500rpm than at 1500. I asked about rpm, not speed. The only reason I mentioned highwasy speed is because typicaly your engine rpm is at 2000 to 2500 for extended periods, giving the force more time to pull things apart if the plate is fractured. But 3500 going up a hill sustains the high level of force for longer than one typically operates there. If I'm at or above 3500, it is usually only for a very short time. But I am there or passing through 3500 on the way to redline very frequently.

Either way, once the plate is heat damaged and fractured, it could probably come apart at any time, under any driving condition, whether sitting at idle or running up to redline momentarily, or cruising at 2300rpm. I would only imagine it to be more severe in terms of exiting the bell housing if moving a little faster. But idle might still be enough. I really have no clue. But that's why I was curious about it.
I see what you were saying and agree
 

_olllllllo_

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I have just over 40,000 miles on my JLUR in a bit over 18 months of ownership. I towed a 5'x10' enclosed U-Haul from Arizona to California on interstate 8 and that involves a couple 4000' climbs and on one section an approximate 8% grade. I was in third gear pulling the trailer (empty) and maintaining about 55-60 mph. Never smelled anything, temps never rose above 220˚. I have also never had an issue with the clutch during all the off-roading I have done, although I did learn that with the 3.6's power curve I generally default to 4LO to make life easy as 4HI can bog the engine in first on steep climbs (over 12%). I just crawl up everything in second gear most commonly unless it is very technical in which case I stay in first until the obstacle eases up.

I do agree with the line of thinking that the software patch is simply a band-aid until the final solution can be developed and rolled out. I just hope that the end solution is as well done as the new steel steering box, because if it is an amazing improvement.
 

JeepCares

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Hi everyone, there has been a lot of questions and different threads so I am going to post this and you may see the same info posted on other threads:

Towing capacity or performance will not be affected by this flash update.

There is no difference in the 3.6L engine's power output under "normal circumstances" with the Y01 flash. The torque reduction only happens if the engine controller calculates the clutch pressure plate temperature is above a certain temperature threshold.

The PCM monitors the engine RPM and the wheel speed sensors to determine if clutch slippage is occurring, how often, and at what intensity. Based on that information, the PCM calculates the clutch pressure plate temperature. The temperature threshold that reduces the engine torque is lower than the temperature needed to do permanent pressure plate damage. The vehicle cannot reach or exceed the temperature threshold under normal operating conditions, including towing and off-roading, and only occurs if the driver repeatedly slips the clutch, performs multiple, consecutive 2nd or 3rd gear launches, or if air is present in the hydraulic clutch system.

Kaitlin
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Wrongful Suspicion

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Hi everyone, there has been a lot of questions and different threads so I am going to post this and you may see the same info posted on other threads:

Towing capacity or performance will not be affected by this flash update.

There is no difference in the 3.6L engine's power output under "normal circumstances" with the Y01 flash. The torque reduction only happens if the engine controller calculates the clutch pressure plate temperature is above a certain temperature threshold.

The PCM monitors the engine RPM and the wheel speed sensors to determine if clutch slippage is occurring, how often, and at what intensity. Based on that information, the PCM calculates the clutch pressure plate temperature. The temperature threshold that reduces the engine torque is lower than the temperature needed to do permanent pressure plate damage. The vehicle cannot reach or exceed the temperature threshold under normal operating conditions, including towing and off-roading, and only occurs if the driver repeatedly slips the clutch, performs multiple, consecutive 2nd or 3rd gear launches, or if air is present in the hydraulic clutch system.

Kaitlin
Jeep Cares
Damn. Kaitlin putting in work. Getting us the information we all so desperately needed. Thank you.
 

Toycrusher

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Hi everyone, there has been a lot of questions and different threads so I am going to post this and you may see the same info posted on other threads:

Towing capacity or performance will not be affected by this flash update.

There is no difference in the 3.6L engine's power output under "normal circumstances" with the Y01 flash. The torque reduction only happens if the engine controller calculates the clutch pressure plate temperature is above a certain temperature threshold.

The PCM monitors the engine RPM and the wheel speed sensors to determine if clutch slippage is occurring, how often, and at what intensity. Based on that information, the PCM calculates the clutch pressure plate temperature. The temperature threshold that reduces the engine torque is lower than the temperature needed to do permanent pressure plate damage. The vehicle cannot reach or exceed the temperature threshold under normal operating conditions, including towing and off-roading, and only occurs if the driver repeatedly slips the clutch, performs multiple, consecutive 2nd or 3rd gear launches, or if air is present in the hydraulic clutch system.

Kaitlin
Jeep Cares
Thanks for the update, however I would have to point out that air in the hydraulic clutch system DOES NOT result in clutch slippage, and even at a light with the clutch held down, could only generate a minimal amount of friction related heat.
 

EMS

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Hi everyone, there has been a lot of questions and different threads so I am going to post this and you may see the same info posted on other threads:

Towing capacity or performance will not be affected by this flash update.

There is no difference in the 3.6L engine's power output under "normal circumstances" with the Y01 flash. The torque reduction only happens if the engine controller calculates the clutch pressure plate temperature is above a certain temperature threshold.

The PCM monitors the engine RPM and the wheel speed sensors to determine if clutch slippage is occurring, how often, and at what intensity. Based on that information, the PCM calculates the clutch pressure plate temperature. The temperature threshold that reduces the engine torque is lower than the temperature needed to do permanent pressure plate damage. The vehicle cannot reach or exceed the temperature threshold under normal operating conditions, including towing and off-roading, and only occurs if the driver repeatedly slips the clutch, performs multiple, consecutive 2nd or 3rd gear launches, or if air is present in the hydraulic clutch system.

Kaitlin
Jeep Cares
...so is FCA saying that all the fires/failures are a result of operator error? No mention here of a possible defect in the clutches themselves.
 

beaups

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Thanks for the update, however I would have to point out that air in the hydraulic clutch system DOES NOT result in clutch slippage, and even at a light with the clutch held down, could only generate a minimal amount of friction related heat.
I think many of us felt this way about FCAs first cause and "fix" for this issue:

1612888766124.png
 

fczabala

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Thanks for the update, however I would have to point out that air in the hydraulic clutch system DOES NOT result in clutch slippage, and even at a light with the clutch held down, could only generate a minimal amount of friction related heat.
 

Toycrusher

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Nice demonstration of what I'm talking about. Air in the line results in a funky pedal feel, but most noticeable, difficulty getting into gear, crunching between gears, or your Jeep still creeping forward with pedal pressed in.

Even if you had this air in the line, and you had to hold your foot on the brake to keep from moving, you would still be generating only a minimal amount of heat with the engine idling at 1100 rpm.
If you then kept your foot on the brake, your other foot on the clutch, and creatively held the throttle at redline, MAYBE you could generate enough heat to get a bad smell.

These pressure plate failures are not operator error. People have been using clutches improperly, to the point of failure, since the clutch was invented, and the damage required clutch replacement and flywheel resurfacing. Pressure plates fracturing and becoming flying shrapnel is a new problem not caused by the same bad drivers. It's a defect
 

fczabala

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...so is FCA saying that all the fires/failures are a result of operator error? No mention here of a possible defect in the clutches themselves.
the way I see it is the first recall addressed their fault (air in the clutch hydraulic system)
and now this recall adds another fail-safe in case operator-fault creates same problem
(plate fracture)
 

EMS

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Nice demonstration of what I'm talking about. Air in the line results in a funky pedal feel, but most noticeable, difficulty getting into gear, crunching between gears, or your Jeep still creeping forward with pedal pressed in.

Even if you had this air in the line, and you had to hold your foot on the brake to keep from moving, you would still be generating only a minimal amount of heat with the engine idling at 1100 rpm.
If you then kept your foot on the brake, your other foot on the clutch, and creatively held the throttle at redline, MAYBE you could generate enough heat to get a bad smell.

These pressure plate failures are not operator error. People have been using clutches improperly, to the point of failure, since the clutch was invented, and the damage required clutch replacement and flywheel resurfacing. Pressure plates fracturing and becoming flying shrapnel is a new problem not caused by the same bad drivers. It's a defect
Here is another interesting question, and maybe the answer will tell us if FCA acknowledges the defect: When the condition is sensed by the PCM, will it throw a "service engine soon" warning to the driver?
 

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