8L90 not shifting from first gear

[loibl customs]

ok so here is what i have... LT1 and 8L90 from a 2018 Camaro installed in a 57 Belair. I am using a stand alone harness from current performance. from day one the transmission would not shift out of first gear... that was then .. Since then i have installed a new ECU,TCU and a new transmission from gm. the TUN procedure has supposedly been successful and both the engine and transmission take commands and tunes from the HP tuner. and on the live data log from the laptop i have seen currant gear go as high as fifth gear but the transmission is not physically shifting. I did just send the stand alone harness back to current performance and they said they didn't find anything wrong but went ahead and rewired the transmission side of things and installed a different fuse center. ... But the transmission still does not shift from first... I am working with Derek @DDtech with the remote tune and he has the engine running great. He has had access to everything and says that if you are only looking at the live data you would think its a perfect running and driving car as all the numbers and readouts look great... I am at a total loss and have thrown way to much money at this issue to not make it work... any suggestions on any possible tricks to make this work would be much appreciated .... Thank You

[TransGo Robert]

ok so here is what i have... LT1 and 8L90 from a 2018 Camaro installed in a 57 Belair. I am using a stand alone harness from current performance. from day one the transmission would not shift out of first gear... that was then .. Since then i have installed a new ECU,TCU and a new transmission from gm. the TUN procedure has supposedly been successful and both the engine and transmission take commands and tunes from the HP tuner. and on the live data log from the laptop i have seen currant gear go as high as fifth gear but the transmission is not physically shifting. I did just send the stand alone harness back to current performance and they said they didn't find anything wrong but went ahead and rewired the transmission side of things and installed a different fuse center. ... But the transmission still does not shift from first... I am working with Derek @DDtech with the remote tune and he has the engine running great. He has had access to everything and says that if you are only looking at the live data you would think its a perfect running and driving car as all the numbers and readouts look great... I am at a total loss and have thrown way to much money at this issue to not make it work... any suggestions on any possible tricks to make this work would be much appreciated .... Thank You

I can't help unless you include a log with all the transmission channels in it. Although I personally am not very good at the tuning side of things, so I don't really need it. But it would probably be wise to also include your tunes so that others with more experience with tuning can look at it and help you figure things out.

[hjtrbo]

No vss or valve stuck codes? Check what dtc's have been disabled. That's all I got.