6R80 Question / Track Only Car

[Leonidas514]

Whats up everybody

Praying that someone has come across a similar issue. I have a 2015 GT with a 6R80 tuned by PBD. I purchased the car in December and have gone through the entire car since then trying to correct this problem. The car has a D1X with a Fore Triple Pump and ID1700 injectors. I have replaced everything on the car, including a brand new PBH trans, brand new convertor, several different tunes, sent logs back and forth and this car still is not shifting right.

First and Second gear are fine, the car shifts at 7600 as it should.

Once it gets to third it seems to do a "fake" shift and the rpms drop but it is still in the same gear. The "fake" shift feels like a shift but on the log, the car is still in 3rd gear and it slowly creeps back up to 7200 and never reaches 7600. Once it shifts into 4th, the rpms drop to 5500 and they stay in the 5000s for the remainder of the pass.

I am leaning towards a faulty PCM, but I have no CEL codes.

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[sigintel]

Some info missing:
Number of miles on D1X?
How often you change trans fluid?
Still on stock steels?
Sounds like friction pack cant hold the shift and it faults out safe.
Make sure you are running both ECU rev limiter and trans shift point/limiter in case trans faults to neutral at WOT.. Ask me how I know...

If you are running stock trans, stock frictions, you should expect eventually the frictions to glaze.
If you have never changed trans fluid/filter for 10k miles FI....

 

[Leonidas514]

Some info missing:
Number of miles on D1X? maybe 3000 on this head unit
How often you change trans fluid? It is a brand new trans literally 1 pass but my old trans did the same thing which is why I changed it
Still on stock steels? Upgraded on both
Sounds like friction pack cant hold the shift and it faults out safe.
Make sure you are running both ECU rev limiter and trans shift point/limiter in case trans faults to neutral at WOT.. Ask me how I know... Ooph. That sucks!

If you are running stock trans, stock frictions, you should expect eventually the frictions to glaze. This trans has billet planetary, input shaft and revers lockout.
If you have never changed trans fluid/filter for 10k miles FI....

 

[sigintel]

If you changed to a new built trans and have exact same problem, sounds like tune.
Double check all the rev/shift limits in tune in case one got bumped down for testing and never got reset... been there too..
Other than that, ask PBH for a tune from them to trouble shoot?
Wait, did you use the same trans as core?
If they reused the same valvebody etc it could have been carried over?
Got nothing else to help. sorry.

 

[Leonidas514]

If you changed to a new built trans and have exact same problem, sounds like tune.
Double check all the rev/shift limits in tune in case one got bumped down for testing and never got reset... been there too..
Other than that, ask PBH for a tune from them to trouble shoot?
Wait, did you use the same trans as core?
If they reused the same valvebody etc it could have been carried over?
Got nothing else to help. sorry.

It was a completely different core. After emailing back and forth with PBD yesterday Rob agreed it was my torque converter locking causing the engine to bog. He sent me a file with the convertor unlocked, so I will try that one. Thanks alot for the suggestions.

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