Builded Nag 1 alwais flare 3-4 shift and short shift

Hi

This is a very long issu I have over few years and I was never able to fix it,
Up to now, tried 3 differant Builded transmission, 2 TCM, rebuilded Torque converter Try to remote tune over 50 TCM tune
from a good Nag 1 tuner and still have the exact same issu.

Tried also a Hemi tuner custom TCM with 3 different flash without succes.

Car is a Magnum SRT8 with a 406Ci Forged Motor with a V-7 Vortec blower at 18 psi, Good 1000 Hp at Motor.

motor tune is solid, no problem there, Transmissionis alwais flaring at 3-4 shift only.
Last winter, instaled another SHR war viking max, all rebuilded to eliminate transmission issue,

Behave perfectlky in the street, Very firm shift at part throttle, then hit the strip to try it safely at WOT,
No change at all, Shift firm 1-2, 2-3, at the commanded RPM but alwais short shift around 5500, 6000, then flare to 6600, then shift.

I am now sure it is not a transmission problem, it seams that the TCM tune is good, Is there somthing in the ECM tune that can cause this behaviour ?

attached TCM and PCM tune
and logAttachment 108573

Attachment 108574
Attached log

Quote:

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Originally Posted by magmax06

Attachment 108574
Attached log

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Hope you find out something. Mine started doing this.

Haven't looked into it yet, (eng coming apart to get forged now), but tuning out was not an option that worked.

1-2 perfect, 2-3 perfect, 3 - like inhale then exhale into 4, 4-5 perfect.

Gonna look into the valve body for starters. Trouble shooting says it's in there, but who knows. they say 3/4 shift valve sticking in the valvebody!

Fluid is clean and not burnt.

Some ones description from 2011

Not disagreeing with anything posted here but I've been looking into this too so I'll share my thoughts... My car has always had a slower shift from 3>4 when compaired to all the other shift changes. It almost acts like a hic-cup shift but I suppose could be described as a flare too.

When our cars shift the shift quality is a result of two opposing pressures in the transmission. The difference (delta P) between Modulation & Shift pressures dictate the speed and firmness of the shift. Higher modulation pressure will apply more holding pressure to the clutches but it also slows down how fast the shift change takes place. Increasing the shift pressure in relation to the Mod pressure will increase how fast the shift change takes place and is felt as being firmer...

On the VTCM monitor (shown below), you can see the control signal sent from the TCM that is controlling the shift pressure (white) and modulation pressure (yellow). Shift pressure is only controlled when a shift is taking place. So we really are only concerned with what we see inside the circles on the graph...

As you can see, the TCM increases Mod pressure at the start of evry shift change. However, the modulation pressure signal increase on the 3>4 shift is much greater then is seen on any of the other shifts. This "spike" in Mod pressure during the start of the 3>4 shift change is what I believe causes the shift flare (in my car anyway). I feel the flare is a result of the stock TCM programming... I'm currently working to overcome this condition...

BTW: Normally the shift pressure would be well below the modulation pressure increase seen at the start of all shift changes... On this graph you can see the shift pressure signal is being held at (or above) the modulation pressure at all times... This is being done by the VTCM system to firm up the shifts... In other words... The shift pressure (during the shift), on these graphs, is a manupulated signal to increase firmness. But the modulation pressure is only being controled by the TCM...

Valvebody
Part Numbers:
52108213A$
Issue Description:
Do not replace the entire Valvebody for an ISOLATED ELECTRICAL ISSUE such as solenoid, speed sensor, or temperature sensor. Also, do not replace the entire Valvebody due to damage of the 13 pin electrical connector. The leadframe itself P.N. 52108308AB contains all the circuitry, speed sensors, and temperature sensors and should be ordered and replaced preventing the unnecessary replacement of the entire Valvebody. In the event of a solenoid fault, you may also want to replace the specified solenoid.


There is a known issue with a 3-4 shift flare or Neutraling out on the 3-4 shift. In most cases this event is accompanied by a P0730, P1731, P0734, and/or P0733 Incorrect Gear Ratio codes. The cause of this event is ferrous or Aluminum debris in the 3-4 Shift Pressure and/or 3-4 Holding valves. Rather than replacing the VB;

1.) Remove the solenoids, leadframe assembly, and bolts securing upper to lower valvebody

2.) Lift upper housing off the VB and turn over. No need to clean the lower housing.

3.) Remove the steel endplate covering the all the 3-4 valves.

4.) Remove the 4 valves and flush out the bores and valves with a solvent such as mineral spirits. Contamination is known to be very small. Hold the housing vertically and flush the bore out generously. Flushing over filter paper (coffee filter) will allow you to observe the debris.

5.) Re-assemble the VB and re-install to roadtest.

6.) Only if the valves are still sticky after the flush or if the 3-4 shift issue persists, should the VB be replaced.

LOP 21-95-01-51 provides 1.2 hours for this repair.

Quote:

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Originally Posted by coanan

Valvebody
Part Numbers:
52108213A$
Issue Description:
Do not replace the entire Valvebody for an ISOLATED ELECTRICAL ISSUE such as solenoid, speed sensor, or temperature sensor. Also, do not replace the entire Valvebody due to damage of the 13 pin electrical connector. The leadframe itself P.N. 52108308AB contains all the circuitry, speed sensors, and temperature sensors and should be ordered and replaced preventing the unnecessary replacement of the entire Valvebody. In the event of a solenoid fault, you may also want to replace the specified solenoid.


There is a known issue with a 3-4 shift flare or Neutraling out on the 3-4 shift. In most cases this event is accompanied by a P0730, P1731, P0734, and/or P0733 Incorrect Gear Ratio codes. The cause of this event is ferrous or Aluminum debris in the 3-4 Shift Pressure and/or 3-4 Holding valves. Rather than replacing the VB;

1.) Remove the solenoids, leadframe assembly, and bolts securing upper to lower valvebody

2.) Lift upper housing off the VB and turn over. No need to clean the lower housing.

3.) Remove the steel endplate covering the all the 3-4 valves.

4.) Remove the 4 valves and flush out the bores and valves with a solvent such as mineral spirits. Contamination is known to be very small. Hold the housing vertically and flush the bore out generously. Flushing over filter paper (coffee filter) will allow you to observe the debris.

5.) Re-assemble the VB and re-install to roadtest.

6.) Only if the valves are still sticky after the flush or if the 3-4 shift issue persists, should the VB be replaced.

LOP 21-95-01-51 provides 1.2 hours for this repair.

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https://d2q1ebiag300ih.cloudfront.ne...=1601055407433

problem is not in the transmission and not in the Valve body.

Already had change those 3 time3?s without no change at all.

I beleive there is somthing between the ECM and TCM that create the problem.
the transmission I currently run is suposed to be able to hold the HP I have.

I am having this issue since the day I started shifting in 4 gears at the quarter miles .

I may have too much torque at the shift and need to apply more torque management.

same issue, but started figuring it out.....

two main causes if you are 100% confident nothing mechanical going on...

Both my recent super pro nag1s have a shift flare on the oncoming gear that is the same gear I lock the converter. So for example if i have my tune set to lock the converter in 3rd gear, during the 3-4 shift it is trying to shift AND lock the converter at the same time and it causes a neutraling. I tested this by changing lockup to 2nd gear, and i had a 2-3 shift flare, nothing 3-4. Seemed pretty consistent. In my logs even though i ask it to lock in 2nd gear, with the power I am making it never happens in the gear I request, goes to "apply" but never "locked" so through the shift change the converter is playing a role in turbine speed. My guess is the converter pressure commanded drops momentarily during the shift, so the converter is screaming to try to lock up as im pulling through the gear, doesnt quite get there, shift command comes and pressure in the torque converter clutches is dropped, rpms spike, shift happens, pressure reapplied, and converter locks and now im in the next gear.

In my latest setup, just from shitty injector data, i ended up with a shitty VE table, which resulted in a shitty modeled airflow, which finally resulted in a stupid calculated torque number (450lb ft versus my actual of 900 or so). Same 2-3 shift flare. However, i recently started to just toss in tweaked injector data so i can steadily keep increasing my VE table, torque is now around 700lb ft and all the shift flares went away.

So this tells me although the ramp torque and tables in the trans max out at 4-500lb ft for modeling, there is still a difference to torque management beyond what is in the table. if your calculated torque is really far off, then the shift commands are going to be off too.

So my suggestion for testing is completely unlock your converter until 5th gear and give it go. If that doesnt help, check your calculated torque, if its way off from your known actual (via a dyno or setup), work on dialing in your VE/injectors to get your aircharge higher so torque comes up in the TCM.

Quote:

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Originally Posted by 06300CSRT8

same issue, but started figuring it out.....

two main causes if you are 100% confident nothing mechanical going on...

Both my recent super pro nag1s have a shift flare on the oncoming gear that is the same gear I lock the converter. So for example if i have my tune set to lock the converter in 3rd gear, during the 3-4 shift it is trying to shift AND lock the converter at the same time and it causes a neutraling. I tested this by changing lockup to 2nd gear, and i had a 2-3 shift flare, nothing 3-4. Seemed pretty consistent. In my logs even though i ask it to lock in 2nd gear, with the power I am making it never happens in the gear I request, goes to "apply" but never "locked" so through the shift change the converter is playing a role in turbine speed. My guess is the converter pressure commanded drops momentarily during the shift, so the converter is screaming to try to lock up as im pulling through the gear, doesnt quite get there, shift command comes and pressure in the torque converter clutches is dropped, rpms spike, shift happens, pressure reapplied, and converter locks and now im in the next gear.

In my latest setup, just from shitty injector data, i ended up with a shitty VE table, which resulted in a shitty modeled airflow, which finally resulted in a stupid calculated torque number (450lb ft versus my actual of 900 or so). Same 2-3 shift flare. However, i recently started to just toss in tweaked injector data so i can steadily keep increasing my VE table, torque is now around 700lb ft and all the shift flares went away.

So this tells me although the ramp torque and tables in the trans max out at 4-500lb ft for modeling, there is still a difference to torque management beyond what is in the table. if your calculated torque is really far off, then the shift commands are going to be off too.

So my suggestion for testing is completely unlock your converter until 5th gear and give it go. If that doesnt help, check your calculated torque, if its way off from your known actual (via a dyno or setup), work on dialing in your VE/injectors to get your aircharge higher so torque comes up in the TCM.

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I
Thanks for the information, it makes sens

I will try on my next time to track to unlock the TC, not really shure how to do it, It alwais show APPLY but alwais slip like yours.

Here the only table I can think, I do not find any tab to Lock or unlock in the TCM,
do I play with the apply TC Speed ?

I can see in the log that it switch from Apply to Slip exactly where it start to flare at the 3-4 shift, then after the 4 gear is engaged it stay in slip Mode till the end of the pull.

Quote:

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Originally Posted by magmax06

I
Thanks for the information, it makes sens

I will try on my next time to track to unlock the TC, not really shure how to do it, It alwais show APPLY but alwais slip like yours.

Here the only table I can think, I do not find any tab to Lock or unlock in the TCM,
do I play with the apply TC Speed ?

I can see in the log that it switch from Apply to Slip exactly where it start to flare at the 3-4 shift, then after the 4 gear is engaged it stay in slip Mode till the end of the pull.

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Yep, Slip means its locked and now targeting the slip rpms you have in your tune in the TCC slip tables.

TC lock and unlock is all in the apply and release tables. you max out the apply tables by gear you dont want it to release in, including setting the release table for the same gear to a very low rpm.

Quote:

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Originally Posted by 06300CSRT8

Yep, Slip means its locked and now targeting the slip rpms you have in your tune in the TCC slip tables.

TC lock and unlock is all in the apply and release tables. you max out the apply tables by gear you dont want it to release in, including setting the release table for the same gear to a very low rpm.

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can we use [ECM] 19645 to up the torque output?i have a jk hellcat, that closes throttle on the 2-3 shift. trans engine torque pid and trans converted engine torque are reporting low 500-400nm at wot

any one?

Quote:

---

Originally Posted by 06300CSRT8

same issue, but started figuring it out.....

two main causes if you are 100% confident nothing mechanical going on...

Both my recent super pro nag1s have a shift flare on the oncoming gear that is the same gear I lock the converter. So for example if i have my tune set to lock the converter in 3rd gear, during the 3-4 shift it is trying to shift AND lock the converter at the same time and it causes a neutraling. I tested this by changing lockup to 2nd gear, and i had a 2-3 shift flare, nothing 3-4. Seemed pretty consistent. In my logs even though i ask it to lock in 2nd gear, with the power I am making it never happens in the gear I request, goes to "apply" but never "locked" so through the shift change the converter is playing a role in turbine speed. My guess is the converter pressure commanded drops momentarily during the shift, so the converter is screaming to try to lock up as im pulling through the gear, doesnt quite get there, shift command comes and pressure in the torque converter clutches is dropped, rpms spike, shift happens, pressure reapplied, and converter locks and now im in the next gear.

In my latest setup, just from shitty injector data, i ended up with a shitty VE table, which resulted in a shitty modeled airflow, which finally resulted in a stupid calculated torque number (450lb ft versus my actual of 900 or so). Same 2-3 shift flare. However, i recently started to just toss in tweaked injector data so i can steadily keep increasing my VE table, torque is now around 700lb ft and all the shift flares went away.

So this tells me although the ramp torque and tables in the trans max out at 4-500lb ft for modeling, there is still a difference to torque management beyond what is in the table. if your calculated torque is really far off, then the shift commands are going to be off too.

So my suggestion for testing is completely unlock your converter until 5th gear and give it go. If that doesnt help, check your calculated torque, if its way off from your known actual (via a dyno or setup), work on dialing in your VE/injectors to get your aircharge higher so torque comes up in the TCM.

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