Harsh Upshifts (esp. in low gears) / P2716 code (shift solenoid 'D') / Recent OEM Pan Replacement... Thoughts? (12 Viewers)

[linuxgod]

I still vote used ecu, especially if they’ll guarantee it works. It’s 1/3 the cost. Those parts rarely fail (I’d say never but I guess this scenario would prove me wrong). But I can’t imagine if a refurbished one worked that it wouldn’t last you for the rest of the life of your truck unless you have something shorting it out, in which case a new ECU would likely die too).

 

[2021 LC200]

The OP thinks he knows and understands and did the trouble shooting right (right…) however is not willing to do the obvious.

The fact that the problem started after the pan and fluid was changed and then gets linked to the ECU is the wrong way of getting back on track. Just the probability of that happening is extremely unlikely.

Dawns on me another way is to drain some fluid at the high side of the Toyota recommended temp window and test drive. Still if that fixes it I would go back to OEM to not mess it up in the longterm.

 

[Matt Hunoval]

I still vote used ecu, especially if they’ll guarantee it works. It’s 1/3 the cost. Those parts rarely fail (I’d say never but I guess this scenario would prove me wrong). But I can’t imagine if a refurbished one worked that it wouldn’t last you for the rest of the life of your truck unless you have something shorting it out, in which case a new ECU would likely die too).

I'm leaning going with the reman PCM / ECM.

Also, to everyone: your input / thoughts have truly been invaluable. As the troubleshooting to find the root cause took 2+ months and various potential failure points were tested & re-tested, with potential failure points being ruled out one by one in a painstaking tedious process... I totally get that some of the potential failure items / parts that have already been ruled out in this long, winding journey of a months-long post & saga got lost / overlooked / forgotten in this Tolstoy-esque thread such that a common refrain remains 'just go back to the OEM pan & Toyota WS ATF fluid.'

Prologue on Toyota WS vs. all others & the analogy to 20-weight oil vs. 30-weight oil.

Dozens / hundreds of others on other threads-- on ih8mud and multiple other forums / sites-- have i) used alternate ATF fluid from multiple non-Toyota OEM manufacturers with as-good-or-better specs than the WS fluid & reported zero issues (up to and including the Amsoil 'Signature Series' 100% synthetic fuel efficient variety I'm using now), so I'm ruling that out as having anything to do with anything & ii) the failure point has now been definitively pinpointed to internal electricals of a now-crapped out PCM / ECM.

Don't want to argue on this specific point re: alternate ATF fluids to use (or not) in the 200 series: for those using the Toyota WS... awesome, it is a great ATF! In sum & I may just be the a******... but it won't be productive to go down the rabbit trail of arguing the specific point of 'if you don't use Toyota WS ATF, your rig will blow up within 20 minutes of turning on the ignition,' as I didn't willy-nilly switch to the Amsoil ATF without going deep into the weeds on the SDS / data sheets on a host of compatible ATF fluids & reading extensive reviews from those who've used it (and others) & had great results.

But I'll use another critically-important fluid by analogy to illustrate why I don't just blindly follow OEM recommendations: consider motor oil-- a 20 weight oil is only recommended in the gasser for the 200 series in two and only two countries among the dozens of countries in which the 200 series is imported & sold. Those 2 outliers: the U.S. & Canada.

For the rest of the world (literally) and across dozens of other countries into which the 200-series is imported & sold, for the exact same configuration / engine, a 30w oil (0 or 5 or 10, depending on climate) is recommended in 90%+ of all countries in which the 200-series is sold. 90%+. Two and only two countries-- the U.S. & Canada-- have a 20 weight oil recommended. And a few outliers recommend 40 weight oil. All for exactly the same petrol engine.

Since I've owned my 200-series & knowing this... I've been running a 5w-30 & it immediately ran quieter & in the long run am confident going with the 30 weight vs. the recommended 20 weight will = a longer engine life, all else being equal.

I'd love to hear someone--anyone-- explain to me how 20 weight oil is better for the longevity of the 200 series than a 30 weight oil, without resorting to 'well, that's just what the manual says, so that's what must be best!' I suspect I'll be waiting, oh, forever to hear a compelling case for 20 weight oil being the 'best' for the longevity of the engine 'just because the manual says so.' These are big, lumberous rigs & need an appropriate weight oil.

See, e.g., GM's very recent & very public sudden shift from most of its large truck & SUV line-up, initially recommending 0w-20 oil but, following a lot of catastrophic failures, switched to recommending 40 weight oil on those exact models post-production and after going thru the initial R&D process in developing those vehicles.

Wonder why?

This long aside isn't about motor oil, of course, but rather: I 100% default to mfg / OEM recommendations as a useful rule of thumb / go-to / heuristic (ATF included) if and only if I've not dug in and done a lot of research into alternatives & have done so in this case in opting to go with the Amsoil. And this isn't dunking on or implying that the Toyota WS ATF is crap-- far from it, it is awesome! But if the SDS data sheets indicate better specs-- even marginally better specs-- then I'm going to seriously consider using an alternative. Again, don't want to re-litigate this specific point narrowly re: ATF fluid as those with differing opinions... well, we can just agree to disagree & that's all good!

 

[Matt Hunoval]

The OP thinks he knows and understands and did the trouble shooting right (right…) however is not willing to do the obvious.

The fact that the problem started after the pan and fluid was changed and then gets linked to the ECU is the wrong way of getting back on track. Just the probability of that happening is extremely unlikely.

Dawns on me another way is to drain some fluid at the high side of the Toyota recommended temp window and test drive. Still if that fixes it I would go back to OEM to not mess it up in the longterm.

think we're talking past each other: how does the above solution address that the sensor / electrical input signals going into the PCM are not making their way to the valve body & the SLT solenoid? Yet when using (whatever the tool was called) & simulating the signal / electrical that the PCM / ECM would otherwise be sending if it were working properly = the SLT solenoid working just fine. I sat there with the owner of the garage & saw this first hand in real-time.

How does going back to OEM ATF fluid magically fix an internal electrical failure of the PCM / ECM? To me & now we know with 100% certainty that the internal electrics of the PCM / ECM sending signals to the SLT solenoid is the root cause... while the root cause = not using OEM fluid seems as plausible of, say, running a tank of 89-octane gas vs the recommended 91 or above, I'll be curious to hear & understand the causal explanation & linkage, as I may well be missing something re: how going back to OEM ATF fluid will magically repair the internal electricals of the PCM / ECM.

 

[Matt Hunoval]

The SLT signal from the ECM/PCM is a pulse modulated signal, so you’d need a PicoScope/oscilloscope to check that properly.

Replace the pan with OEM and use Toyota WS fluid and go from there.

thx for reminding me of the terminology-- the picoscope / oscilloscope was used to send a signal into the FRONT-end & detached wiring harness leaving the ECM / PCM to the valve body & SLT solenoid & it worked fine. When plugging into the BACK of the PCM / ECM, the signal wasn't running thru / being processed correctly by the ECM / PCM so that the proper signal was being sent from the front wiring harness connection point to the valve body & to the SLT to trigger it to function.

THAT is the failure point we've now definitively identified & appreciate your refreshing my memory on the name of the tool used.

 

[GrouchyTech]

thx for reminding me of the terminology-- the picoscope / oscilloscope was used to send a signal into the FRONT-end & detached wiring harness leaving the ECM / PCM to the valve body & SLT solenoid & it worked fine. When plugging into the BACK of the PCM / ECM, the signal wasn't running thru / being processed correctly by the ECM / PCM so that the proper signal was being sent from the front wiring harness connection point to the valve body & to the SLT to trigger it to function.

THAT is the failure point we've now definitively identified & appreciate your refreshing my memory on the name of the tool used.

The ECM bases its output to the TCM on many different things. I’m not certain you CAN force an output. The signal the ECM outputs is a pulsed waveform.
But what you could do is active test the SLT solenoid via GTS+ (“Techstream”) and see what happens with that.
The solenoid codes aren’t based off the solenoids themselves operating, it’s based on what happens inside the transmission after whichever signal is sent to it. So, you can still get the SLT code even if it’s working fine and has some junk in the valve body (or some other issue) preventing it from controlling line pressure properly.

 

[2021 LC200]

think we're talking past each other: how does the above solution address that the sensor / electrical input signals going into the PCM are not making their way to the valve body & the SLT solenoid? Yet when using (whatever the tool was called) & simulating the signal / electrical that the PCM / ECM would otherwise be sending if it were working properly = the SLT solenoid working just fine. I sat there with the owner of the garage & saw this first hand in real-time.

How does going back to OEM ATF fluid magically fix an internal electrical failure of the PCM / ECM? To me & now we know with 100% certainty that the internal electrics of the PCM / ECM sending signals to the SLT solenoid is the root cause... while the root cause = not using OEM fluid seems as plausible of, say, running a tank of 89-octane gas vs the recommended 91 or above, I'll be curious to hear & understand the causal explanation & linkage, as I may well be missing something re: how going back to OEM ATF fluid will magically repair the internal electricals of the PCM / ECM.

Yes we are. Did you fix your issue yet…?

 

[yeLwWm]

1. New oil pan hold extra 5qt oil when temp reach 90C(running temp) 5qt will bt 5.27 qt. Seems not a big deal.
2. If you gonna replace some solenoids, choose ROSTRA, it's much cheap. And usually there will more than one solenoid worn out. I suggest you change all solenoid at once, with Rostra it's about $800 change all nine solenoids.

2010 transmission codes p2714 & p0761

Hey guys, been referencing this forum for a number of years but first time posting a question. I have a 2010 Toyota tundra SR5 5.7 4x4 with the AB60F...

www.tundras.com

 

[Matt Hunoval]

View attachment 3959866

1. New oil pan hold extra 5qt oil when temp reach 90C(running temp) 5qt will bt 5.27 qt. Seems not a big deal.
2. If you gonna replace some solenoids, choose ROSTRA, it's much cheap. And usually there will more than one solenoid worn out. I suggest you change all solenoid at once, with Rostra it's about $800 change all nine solenoids.

2010 transmission codes p2714 & p0761

Hey guys, been referencing this forum for a number of years but first time posting a question. I have a 2010 Toyota tundra SR5 5.7 4x4 with the AB60F...

www.tundras.com

Not to get pedantic but accepting the invitation to get to that level of pedantic precision with the above nice, neat science textbook equations, several real world variable departures from the artificial lab excitement data: a) the above formulas are premised on 5qts & my 2013 570 with the tow package has a dry 12.3 qt capacity (ie almost 2.5x greater) & b) with the B&M pan’s extra 3.5qts, it raises the cumulative capacity to 15.8qts, or a bit over the 3x 5qts. b) I live in the south and I never see a delta at operating temps of 60C, or 140F. Currently in the summer I’m starting at an ambient temp of 80F and my trans temps with the extra fluid and therefore heat-soaking / dissipating dynamics = my trans temps operating in the 184-189 range (don’t tow, as I have a diesel pickup for that). So my trans temp delta is around 100F, or 38C. Haven’t run the math to derive an expansion of volume level to the thousandth decimal place & will defer to others to do the number crunching to arrive at the expanded volume to 3-5 decimal places, but 1) as the OEM solution would be subject to the exact same thermodynamic fluid physics but 2) as I have greater volume but run at cooler temps… my guess is the delta between each is de minimis at most (quick math in my head maybe 0.1 qt delta at full operating temps when offsetting increased volume by lower temps)… I agree with the science textbook math, sure thing. But these rigs ain’t F1 race cars custom-built by Ferrari with extremely tight tolerances across all operating parameters, nor failing / blowing up due to running some de minimis lesser or greater ATF fluid due to fluid dynamic expansion within that tight of a tolerance. The physics outlined in a vacuum are correct for a 10th grade science test Q, but not especially compelling nor illuminating as applied in the 200-series platform under real world operating conditions…no?

 

[Matt Hunoval]

Not to get pedantic but accepting the invitation to get to that level of pedantic precision with the above nice, neat science textbook equations, several real world variable departures from the artificial lab excitement data: a) the above formulas are premised on 5qts & my 2013 570 with the tow package has a dry 12.3 qt capacity (ie almost 2.5x greater) & b) with the B&M pan’s extra 3.5qts, it raises the cumulative capacity to 15.8qts, or a bit over the 3x 5qts. b) I live in the south and I never see a delta at operating temps of 60C, or 140F. Currently in the summer I’m starting at an ambient temp of 80F and my trans temps with the extra fluid and therefore heat-soaking / dissipating dynamics = my trans temps operating in the 184-189 range (don’t tow, as I have a diesel pickup for that). So my trans temp delta is around 100F, or 38C. Haven’t run the math to derive an expansion of volume level to the thousandth decimal place & will defer to others to do the number crunching to arrive at the expanded volume to 3-5 decimal places, but 1) as the OEM solution would be subject to the exact same thermodynamic fluid physics but 2) as I have greater volume but run at cooler temps… my guess is the delta between each is de minimis at most (quick math in my head maybe 0.1 qt delta at full operating temps when offsetting increased volume by lower temps)… I agree with the science textbook math, sure thing. But these rigs ain’t F1 race cars custom-built by Ferrari with extremely tight tolerances across all operating parameters, nor failing / blowing up due to running some de minimis lesser or greater ATF fluid due to fluid dynamic expansion within that tight of a tolerance. The physics outlined in a vacuum are correct for a 10th grade science test Q, but not especially compelling nor illuminating as applied in the 200-series platform under real world operating conditions…no?

I know that the math isn’t your point btw: you’re agreeing w me that a previous poster’s chest-beating trump card re increased fluid pressure fundamentally misunderstands, well, basic science. To your direct point re replacing all of the solenoids…!contemplated it for PM reasons but the only solenoid for which i was getting an error code was only the SLT solenoid & the symptoms presented were consistent with a crapped out / malfunctioning SLT solenoid. So just replaced the single SLT solenoid. Aaaargh….!transmission internals voodoo is quite opaque indeed!

 

[Matt Hunoval]

Yes we are. Did you fix your issue yet…?

No but I await a compelling explanation as to how reverting back to OEM ATF fluid will fix the internal electronics of the ECM/PCM, as that was your solution. I suspect I’ll be waiting , oh, forever for that explanation. Note you didn’t respond at all— your answer was just a snarky & unrelated deflection when pressed.

 

[2021 LC200]

Well, you are not listening to engineering and scientific logic and your long replies go down rabbit holes trying to defend something which several of us observe as not the way forward. We just want to help you trouble shoot. Other opinions and experiences I find very helpful. Reason I participate in this forum as I learn a lot even though I know a fair bit having a Masters in Mech Engineering. Seems though you are not open to them, so why ask for help in the first place? Perhaps tell us what you figured out once it is fixed, as we are not getting to you.

Bottomline it is your issue and I wish you good luck.

 

[2021 LC200]

No but I await a compelling explanation as to how reverting back to OEM ATF fluid will fix the internal electronics of the ECM/PCM, as that was your solution. I suspect I’ll be waiting , oh, forever for that explanation. Note you didn’t respond at all— your answer was just a snarky & unrelated deflection when pressed.

@GrouchyTech already explained why your ECM/PCM troubleshooting maybe leading to the wrong conclusion, i.e. not giving you the in and outputs the way the transmission and ECM/PCM normally work together.

 

[GrouchyTech]

No but I await a compelling explanation as to how reverting back to OEM ATF fluid will fix the internal electronics of the ECM/PCM, as that was your solution. I suspect I’ll be waiting , oh, forever for that explanation. Note you didn’t respond at all— your answer was just a snarky & unrelated deflection when pressed.

I certainly don’t know everything, so I ran this scenario by a few of my coworkers and they ALL immediately asked if you have already reinstalled the original pan and if it has Toyota WS.

It seems like you are holding fast to shotgunning an ECM at this problem. I’m not sold on the idea, but if it works you’ll get to say “I told you so!”

However, if this were my own vehicle, I wouldn’t immediately consider replacing the ECM. I am not familiar with how to command the ECM to output a waveform to the SLT solenoid by using the PicoScope. But, GTS+/TechStream or other diagnostic tools can force operation via an active test—which may have been exactly what you did and maybe I’m just misunderstanding.

I would replace the pan with the original one, perform a few drain/fills with Toyota WS and set the level, and then active test the SLT solenoid, check the line pressure, and compare the input and output shaft speeds.

 

[bloc]

Does this aftermarket pan have the same level-check procedure as stock?

If so, has anyone verified that the top of the level-check tube is the same distance below the pan flange as stock?

As an aside, the US-market 200-series has a very robust transmission cooling strategy, and quite a bit of fluid volume given the GCWR. I’d be shocked if this mod made a substantive difference on fluid temp or lifespan, outside of maybe consistent very heavy towing use case.

 

[gasman4u]

Does this aftermarket pan have the same level-check procedure as stock?

If so, has anyone verified that the top of the level-check tube is the same distance below the pan flange as stock?

As an aside, the US-market 200-series has a very robust transmission cooling strategy, and quite a bit of fluid volume given the GCWR. I’d be shocked if this mod made a substantive difference on fluid temp or lifespan, outside of maybe consistent very heavy towing use case.

That’s the rub imo. I doubt it’s the fluid selection, but rather the “height” or volume relative to stock pan standpipe level when appropriately checked.

OP, post whatever you ultimately do as it sounds like we aren’t able to help.

 

[burtlively]

Every one of you are smarter than me I guarantee it. An inconvenient truth that I’ve learned in my time on this forum is that many times when transmission issues arise whatsoever on this platform, you are better served by replacing the transmission rather than going down all these rabbit holes. I have been there and done that. I spent way too much time and money when I should’ve just replaced it. As @GrouchyTech has stated, the only thing reman on a transmission is the body itself. All new solenoids, torque converter, etc. It costs $3500 after core. That’s less than you’d pay for the solenoids alone. I realize $700 is way less than $3-$4K, but I can tell you from experience I bought solenoids, valve body, transmission drain & fill, and a few other tricks. In addition to having my truck unavailable for a couple months I wasted around $3,000 in total going down rabbit holes when I could’ve just grabbed a new transmission and had it bolted up for a little more. I realize everyone wants to try to fix the problem for less, but as I learned from the folks on this forum I should’ve just taken their advice and it would’ve saved me a lot of time and money. Just my experience. I hope you get things squared away!