Do a search. This isn't the only thread with similar findings. To me it isn't a trans slippage. It's like the car is suddenly going into a limp mode and gradually recovers. The two times I recall it happening is turning left and gunning it so probably 2nd or 3rd gear engagement. As far as Adam of ZFG trying to look at Livernois datalog... makes me wonder..
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Hard launch transmission disengages
- Thread starter 21booSTedExplorer
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I will put my money on some sort of trans slippage. To try to help, I looked at the service manual. It lists either the TCC (torque converter clutch) or the : Low One-Way Clutch Assembly as possible problems. Here is the link:
https://www.liaviator2.com/lincoln_aviator_diagnosis_and_testing_diagnosis_by_symptom-2724.html
In another part of the trans diagnostics, it also lists the fact that many of the trans DTCs will not be set unless it sees consecutive events according to the service manual- which suggests why diagnosing this problem is difficult.
Most performance based automatic transmission diagnostic trouble codes (DTCs) require the fault to be detected multiple times before setting a DTC. In many instances the fault must be detected consecutively a predetermined number of times (up to five). Carrying out the shift point road test as detailed below increases the likelihood that a DTC will set if a fault is present in the system.
The link to that page:
https://www.liaviator2.com/lincoln_aviator_diagnosis_and_testing_road_testing_vehicle-2721.html
The last time I worked on an auto transmission was a 700R4- late '80s. The 10R60- just looking at the codes and specs- is so far beyond that it might as well have a hyperdrive!
https://www.liaviator2.com/lincoln_aviator_diagnosis_and_testing_diagnosis_by_symptom-2724.html
In another part of the trans diagnostics, it also lists the fact that many of the trans DTCs will not be set unless it sees consecutive events according to the service manual- which suggests why diagnosing this problem is difficult.
Most performance based automatic transmission diagnostic trouble codes (DTCs) require the fault to be detected multiple times before setting a DTC. In many instances the fault must be detected consecutively a predetermined number of times (up to five). Carrying out the shift point road test as detailed below increases the likelihood that a DTC will set if a fault is present in the system.
The link to that page:
https://www.liaviator2.com/lincoln_aviator_diagnosis_and_testing_road_testing_vehicle-2721.html
The last time I worked on an auto transmission was a 700R4- late '80s. The 10R60- just looking at the codes and specs- is so far beyond that it might as well have a hyperdrive!
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And not to pile on, but having read through the relevant sections of the manual, if I'm right on the clutch slippage, repeating this is NOT going to be a good thing for the trans. (See post #16). Slipping clutches will end up burning lining material which will end up in the trans fluid. That contamination will lead to even worse consequences.
Hey, I may be wrong. But I don't think I am.
Hey, I may be wrong. But I don't think I am.
To provoke some convo, and for the "conspiracy" theorists out there. After examining the service manual, I can't find anything related to a TCM torque control strategy that would cause an ECU fault mode (reduce torque). However, the TCM can adjust the slippage in the torque converter and measure it precisely i.e. it can "slip the clutch" when needed.
Is it possible that Ford has adjusted the TCM (affecting TCC or Low One-way Clutch ) to limit torque due to the 3/4 bolt issues on later model vehicles? I am NOT saying this is the case, but if the torque being transferred to the output shaft were limited via clutch slippage it would certainly help alleviate rear diff failures. This would explain perfectly the trans slippage while "bumping off the rev limiter".
The only way to test this theory would be some sort of logging of the TC_SLIPDSD and TC_SLIPACT in the '22 models and compare against a '20 model. Difficult to do.
Just a thought, but before posting any old opinion, refer to the service manual pages in post #42 and read all about it. Then keep reading for the next several diagnostic pages.
If this is indeed the case, it very well could be that it was a "red herring" to flash purely for the parking brake engagement. This is all conjecture, but it certainly would be an inexpensive way for Ford to deal with a possibly fatal differential mounting failure at the lowest possible cost. If that's the case, and you have a later year vehicle or one that's had that done and you're modifying your vehicle, you're SOL.
Is it possible that Ford has adjusted the TCM (affecting TCC or Low One-way Clutch ) to limit torque due to the 3/4 bolt issues on later model vehicles? I am NOT saying this is the case, but if the torque being transferred to the output shaft were limited via clutch slippage it would certainly help alleviate rear diff failures. This would explain perfectly the trans slippage while "bumping off the rev limiter".
The only way to test this theory would be some sort of logging of the TC_SLIPDSD and TC_SLIPACT in the '22 models and compare against a '20 model. Difficult to do.
Just a thought, but before posting any old opinion, refer to the service manual pages in post #42 and read all about it. Then keep reading for the next several diagnostic pages.
If this is indeed the case, it very well could be that it was a "red herring" to flash purely for the parking brake engagement. This is all conjecture, but it certainly would be an inexpensive way for Ford to deal with a possibly fatal differential mounting failure at the lowest possible cost. If that's the case, and you have a later year vehicle or one that's had that done and you're modifying your vehicle, you're SOL.
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OP
Thread Starter
#47
Thread Starter
#47
Great theories and input on the thread, thank you for sharing all your findings. Mine is a 2021 but it is an early 2021. It was the very beginning of the 3 bolt configuration but bought before the recall. I have not taken it in since I have the diffy stiffy I feel like I would rather not add the step of turning off the parking brake every time I drive anywhere. I'm aware they still break with the FenFab part on there but I've also read they break on the 2.3L models under normal acceleration as well so with the added brace I'm willing to roll the dice on that matter. My point is I shouldn't have any software pertaining to the rear diff issue unless Ford already had it in there from the factory at the point of redesign and it's just not a flawless fix but may be reducing the rate of failures. I ordered my MPVI3 and 2 tunes from ZFG last week, got my device and sent my stock file Thursday night. Curious to see if a ZFG 93 tune will outrun the LMS E30 stage 4 tune. Then we test the E50 and really hurt some feelings.
I have the same issues sometimes as I thought it was the traction control activating.
I made sure the TC was turned off and from time to time it launched hard then disengaged and "bogged" down until I let off gas. Once again as others have said doesn't happen all the time.
As far as times, I ran a 12.25 with a 5-star e50 tune, stock intercooler and full thermal 2.5 exhaust. Spare/jack removed with 1/4 tank. Draggy timed.
The 12.25 was achieved in fall temps of 55-60 degrees.
I have added the AFE intake and a lower temp thermostat since and am waiting for my CV Fab intercooler too arrive.
Hopefully once added I can get into high 11's.
I made sure the TC was turned off and from time to time it launched hard then disengaged and "bogged" down until I let off gas. Once again as others have said doesn't happen all the time.
As far as times, I ran a 12.25 with a 5-star e50 tune, stock intercooler and full thermal 2.5 exhaust. Spare/jack removed with 1/4 tank. Draggy timed.
The 12.25 was achieved in fall temps of 55-60 degrees.
I have added the AFE intake and a lower temp thermostat since and am waiting for my CV Fab intercooler too arrive.
Hopefully once added I can get into high 11's.
Just happened to me today. Hard launch, spun tires, and when it tried to shift to 2nd or 3rd, I lost all power and throttle for ~ 2 seconds while the vehicle recovered. Thought I had forgotten I was in manual mode and failed to shift at first. Definitely auto. No codes yet.
I was spinning/hopping quite a bit, I had traction control OFF and AdvanceTrack ON.
I was spinning/hopping quite a bit, I had traction control OFF and AdvanceTrack ON.
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The power shut down is different than the "bouncing off the rev-limiter" problem. In the case of loss of power, my guess is this is some form of traction control (enabled or not) stepping in. Think about what the ECU is seeing- since the ST does not have LSDs on either axle, there is a big disparity between the speed sensors on each wheel per axle as well as likely big differences between axles if wheel hop occurs. It is also not seeing any steering angle (I assume you're going straight?). This is probably enough to invoke a "fail safe" power shutdown.
Yeah, I don't think I was bouncing off the rev-limiter. Just hopping a lot. Was going in a straight line. Will launch at lower RPMs from now on, scared me a bit. I thought that bolt had snapped or something at first lol.
That was also the first time I had that much wheel hop. Holy cow, these turbos are behaving much, much differently in the cooler weather. Been "oh shit" braking on colder mornings lately
That was also the first time I had that much wheel hop. Holy cow, these turbos are behaving much, much differently in the cooler weather. Been "oh shit" braking on colder mornings lately
Anyone figured anything out on this? I am having this problem as well intermittently. Sometimes If I launch it with any RPM the trans seems to hold 1st, cut power, and bang off the rev limiter. I also thought I was spinning at one point or hitting the traction control but I confirmed this weekend the TC was shut off and this happened twice on two separate occasions. One time was off a light and the car was fully warmed up. Held at 2000 RPM and ripped from a light and it did it, the other time I was rolling at 20 and punched it and it did it as well. Will try to data log it and send to ZFG when I can. Was hoping someone figured it out at this point.
Tuned ZFG 93 with e30 and I am in Michigan so its colder. I would also agree that this seems to happen only in cooler weather as I never had this happen in the summer.
Tuned ZFG 93 with e30 and I am in Michigan so its colder. I would also agree that this seems to happen only in cooler weather as I never had this happen in the summer.
OP
Thread Starter
#54
Thread Starter
#54
Mine has been down for the last month with a coolant leak. It goes to Ford on Wednesday but with the holiday I'm not expecting it back too quickly. If you can datalog it that would be our best chance at finding the cause and if Adam can do anything about it through a tune. Initially it seemed like it was only stock or LMS Tuned vehicles so I was wanting to test more now that I've gone to ZFG but it went down shortly after I put in the baseline tune. It may be something beyond a Tuners control but definitely worth trying to document data on and have him investigate.
I don't think there's any doubt that the behaviors are caused by the ECU/TCU trying to save the engine, trans or (possibly) occupants. For example, an overboost situation would cut power, a traction control (spinning) would cut power, and an over torque on the trans would likely slip the torque converter to save the transmission. Some of you may be experiencing more than one of these conditions at the same time which would explain the various descriptions. You're just outside the limits set by the engineers.
If it is a torque related issue, then the easy remedy would be to have the tuner adjust the wastegate PID settings to soften the boost reponse at low RPM.
If it is a torque related issue, then the easy remedy would be to have the tuner adjust the wastegate PID settings to soften the boost reponse at low RPM.
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My 2020 ST started knocking 2 days ago on morning cold start.
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