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Discussion Starter #1
Tranny *seems* to be working normally (temperature, forward, and reverse). However, when I engage Tow/Haul mode, after the 1st shift, the Tow/Haul light begins flashing. Everything still seems to work nominally (reverse, low range, tow/haul) except I think I'm starting in 2nd gear from a stop.

Here are the codes I read:

P0771 - Powertrain
Shift Solenoid "E" Performance or Stuck Off
P2704 - Powertrain
Trans Friction Element E Apply Time Range/Ref

Solenoid E is for low/reverse. Reverse works, although it engages a bit more harsh than before, but nothing anyone else would notice. Low range seems fine.

This started when I returned to my DD SCT Innovative tune after removing the TowMax SCT Innovative tune during the summer season. Things I've tried: disconnect batteries/drained KAM; reflashed, checked fluid and level; all clean and good.

Advice? Should I drop the pan and replace SSPC-E solenoid? Pressure switch? Should I swap the DD SSPC-D solenoid for an aftermarket one while I'm in there? TFT sensor?

Thank you!
 

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If the transm is still acting up with a different tune loaded, then your approach of dropping the pan and replacing solenoids and sensor is probably a good idea. The inside bottom of the pan once dropped is always a good indicator of transm health, slight metallic and minimal dark fine clutch material is normal, but if you find any chunks of debri or large metallic flakes, then that could spell teardown.

You can also remove the bypass canister transm filter up under the passenger side radiator area and see what is looks like inside, and of course replace it as well.

My tow haul wires shorted out in my shift lever-column last summer, but that blew the fuse for the instrument cluster and the transm still shifted normal but had no tow haul function.

It is kinda coincidental that this all happened after reloading your DD tune, but maybe the higher power tune enhanced an issue that was already lurking.

Good luck and keep us posted.

Harry
 
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Discussion Starter #3
Returned to stock tune. As before, tranny runs perfectly normal until I select Tow/Haul mode. Then once it shifts into 2nd, Tow/Haul starts blinking and when I stop, it stays in 2nd gear. Only difference now is the truck runs in limp mode. With the ID tune, it didn't limp, just flash Tow/Haul. Same error codes.

I ordered parts and will update when I get the pan dropped.

Thanks.
 
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Discussion Starter #4
Update

Parts finally all arrived.

1) Dropped the pan. It could not have been more clean! (attached picture) Good news.
2) Replaced TFT sensor, SSPC-E, pan filter, and bypass filter.
3) Installed a PTP Modified Direct Clutch Solenoid in place of SSPC-D.
4) Filled with new Mercon SP.

However, the problem still exists. In Tow/Haul mode, when it shifts into 2nd, Tow/Haul starts blinking and it doesn't shift below 2nd when I stop. Tow/Haul seems to work when I turn it on in 6th gear; downshifts normally. But when I stop and start again in Tow/Haul, the problem pops up.

Also, I expected I would need to adjust my ID tune shift pressures down with the PTP solenoid. But I can't really tell the modified solenoid difference in shifting.

Thanks for any further advice!
 

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Discussion Starter #5 (Edited)
More testing....

I found that when I start in Tow/Haul mode and accelerate from a stop, the problem does *not* exhibit itself. It's when I'm in Tow/Haul and coast downhill that it fails when shifting into 2nd gear. My house is on a little hill so the downhill deal is my typical run.

Wire chafing somewhere? Steering column? Under the truck?
SSPC-E pressure switch (which I did not replace)?
I hope it isn't the tranny fluid pump. That's deep in the tranny.

Same error codes as in the OP.

Thanks for any advice or suggestions anybody can offer.
 
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I found this info below here, even though you probably have already found it too...
https://www.motorcraftservice.com/vdirs/diagnostics/pdf/DOBDSM804_64.pdf
it's for the 6.4L, but it has a ton of info about the 5R110W starting on page 54.

I copied the section with your codes below...

Low/Reverse Clutch (SSE) P2704 Transmission Friction Element E apply time range/performance.
P0771 Shift Solenoid E Performance or Stuck Off
P0772 Shift Solenoid E Stuck On
Gears are enabled/disabled based on clutch faults. Example: if the OD clutch is failed off, all gears requiring the ODC to
be on are disabled (2nd, 4th, and 6th gear). If the OD clutch is failed on, only gears with the ODC on are commanded
(only 2nd, 4th, or 6th gear will be commanded, 1st, 3rd, and 5th will be disabled).

It's weird how this is all only triggered after tow haul usage. We have speed sensor failures on our MBZ transm's, they are integrated into the electronic conductor plate that all the solenoids are mounted onto. Not sure if the 5R110W is even remotely similar. But it causes intermittent limp home conditions which keeps it in second gear until you pull over and cycle the key on-off and start driving again.

So after rereading your last post, it occurs only after tow haul downshifts to second, correct?

I'll try to find out more, and maybe someone else on here will chime in with some helpful info too.

Harry
 
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Discussion Starter #8
Big thanks!

The document does contain good info. I hope we can assume the TCM in our trucks operates similarly. In my case (from page 61):

Code:
Low/Reverse Clutch System (functional test of SSE):

DTCs
P2704 Low Reverse Clutch Failed On or Off
P0771 Low Reverse Clutch Failed Off
P0772 Low Reverse Clutch Failed On

Monitor execution
LRC failed off – detected in 1M or 2M.
LRC failed on – detected during upshifts from 1st or 2nd to any higher gear, tested in 1st or 2nd after a bad shift event.

Monitor Sequence
Tested in the steady state gear listed above, then after each bad event the clutch is cycled and tested again

Sensors OK
ISS, OSS

Monitoring Duration
3 bad events
In Tow/Haul mode, it uses the LRC (SSE). I'm getting P0771 "Low Reverse Clutch Failed Off". So it's detected in 1M or 2M. I'm not sure what the 'M' means, but I suspect this is just in 1st or 2nd gear.

To detect this, it's using the ISS and OSS sensors. Since the tranny *seems* to shift normally, this would indicate bad feedback from the ISS or OSS sensors.

However, if that's the case, why aren't I getting the DTCs for either the ISS or OSS?

Thanks again!!
 

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Just to clarify so we stay on the same page, the problem surfaces during the 3-2 downshift only in tow-haul, but does not do it when not using tow-haul.

Harry
 

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Discussion Starter #10
Just to clarify so we stay on the same page, the problem surfaces during the 3-2 downshift only in tow-haul, but does not do it when not using tow-haul.

Harry
It surfaces only in tow/haul, and when it coasts in 2nd gear. I've found when I accelerate in tow/haul passed 2nd, it doesn't do it. Only when I try to use engine braking in 2nd gear.

Once the tow/haul starts blinking, the tranny never shifts back to 1st when stopped. Other than that, there are no other noticeable limitations (although stock tune puts me in limp mode).

Thanks!
 
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As we know, anytime the tow haul starts blinking it means a transm malfunction or fault.

I wish I had a good answer for you. But my guess is, whatever gearing and functions are applied during the 2nd gear coasting in tow haul is where the fault is surfacing due to those particular load conditions on the transm. Could be electrical, could be mechanical. Your oil pan was exceptionally clean which is a great thing, and just adds further to the mystery, as one would expect some type of debris showing if there was a mechanical issue.

We need a 5R110W transm specialist to chime in with some insight. I'll keep searching for a possible answer.

Harry
 
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Discussion Starter #12
Thanks for your help! Always a pleasure Harry.
 
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Discussion Starter #13
Just an update on this anomoly:

Since replacing solenoid-E, -D (aftermarket), TFT sensor, and of course filters and fluid. I've noticed that the problem now only appears to surface when truck is cold. My tranny fluid level is *exactly* where it is supposed to be per the stick hot and cold markers. But I'm wondering if I should add more fluid anyway? Thoughts?

I'm also wondering if I should have replaced pressure switch E while I had the pan dropped. :damnit

Thanks for suggestions.
 

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The mercon sp fluid is what is being recommended again, the mercon lv fluid is what I currently have in my transm, but I have not had any issues running either fluid. I don't recommend overfilling any transm fluid level due to the fluid aeration issues which it can cause.

I'm not sure where to go from here, but usually intermittent transm issues are valve body related or internal seal or clearance wear conditions that change with temps.

Harry
 

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Discussion Starter #15
Here's another development that been looming, but now I've confirmed it. When I punch it (WOT) in TOW/HAUL it won't shift past second, just rev limits. There is no blinking TOW/HAUL light. When I accelerate light/normal/heavy it shifts fine. Of course, I'm warmed up to NOT before punching it.

The previous problem from the OP still occurs. I took apart the steering column and didn't see even the slightest bit of wear on the TOW/HAUL wires.
 
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There have been a few threads like yours surface in the last few months. One thing that seems to pop up as a "root cause" is a failing pump. Failing pumps can result in more damage also.

You can hook up a pressure gauge to it and see what it is doing. From what I read, it might be hard to interpret the data though. Might be something to try anyway.

I can post some links to the gauge install, the expected values, and a few links to videos - if you would like.

A knowledgeable TorqShift person has stated that the only reason for the code is a stuck solenoid, but the more I read, the more I am convinced there is a root cause - since solenoid replacement just doesn't seem to help.
 

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I have torn a few transm down in my day, but never a torqshift, but from the ones I have...

Internal seals worn, too much clutch pack clearance, worn hard parts, valve body conductor plate or solenoid issues, housing warped, bushings or bearing loose, all can contribute to intermittent malfunctions under the right conditions.

A pressure test like Mark is talking about can reveal important line pressure and pump specs, but also an air test with the valve body removed and pressurizing the transm housing ports that the valve body feeds in-out of can reveal any air leakage from worn seals in the servos, and also listen for a good thunk of clutch pack engagement with no leakage sounds. We use a leakdown tester setup when doing this and don't like to see anything over 1% leakdown.

But this could also just be some weird electrical glitch or wiring issue too.

I have no answer at this point, but am curious as heck as too what is causing this.


Harry
 
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Discussion Starter #18
A knowledgeable TorqShift person has stated that the only reason for the code is a stuck solenoid, but the more I read, the more I am convinced there is a root cause - since solenoid replacement just doesn't seem to help.
Thank you Bismic. When I removed the "bad" solenoid, I couldn't measure (ohms) or tell anything was wrong with it. It cycled just fine with a benchtop battery.

I've seen videos of the pressure test on youtube. Sounds like that's next on my list. I was hoping not to go there as the fluid pump is deep in the tranny (and expensive). :(
 

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Discussion Starter #19 (Edited)
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Discussion Starter #20
Update

I dropped the pan *again* and also the valve body. I replaced the PCA solenoid. Supposedly the one solenoid to rule them all. I also measured the resistance (ohms) on all the solenoids. All measure correctly (attached picture).

Results? Yea, it sucks. This repair seems to have exacerbated the problems. Now I can get the fault to occur almost every time I coast in 2nd gear. Again, only in Tow/Haul mode. Regular mode seems great. Anyway, once the fault occurs (Tow/Haul blinks), the tranny won't drop to 1st gear. I start in 2nd, shifts up fine. Park works, reverse works, but when I shift to D or 1st, I'm starting in 2nd. A restart solves the problem.

Also in Tow/Haul, it frequently won't shift past 2nd while accelerating. Once I stop, sometimes it'll work the next time.
 

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