Built 5spd inconsistent 3-4 issue, still learning?

LSxBakakos

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May 29, 2022
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Definitely sounds like it was a fun truck but expensive one too lol. This is my second trans and for what this one costed I can't imagine replacing em often. By any chance would you know if that would work? One mode for dailyish activities t/h on for the biggest tune? Just thinking out loud if there's two different sets of taps. Will say though the way it acted the other day without it on it actually felt faster, very well could've just been the learned parameters though
 

Chevy1925

don't know sh!t about IFS
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Definitely sounds like it was a fun truck but expensive one too lol. This is my second trans and for what this one costed I can't imagine replacing em often. By any chance would you know if that would work? One mode for dailyish activities t/h on for the biggest tune? Just thinking out loud if there's two different sets of taps. Will say though the way it acted the other day without it on it actually felt faster, very well could've just been the learned parameters though
yes that helps but its not 100% fool proof. after digging around in the hex files by an ex friend, he was finding it wasnt a clear cut deal. There was still sharing of some adapts between reg and t/h mode. i would certainly do that though. a good defueling tune is key as well.
 

LSxBakakos

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May 29, 2022
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Thank you sir, appreciate the help. And just to clarify do you mean defuel as in detorqued? Or as in defueled shifts? Tunes are detorqued, but I don't think there's much defueling left. Trans isn't harsh by any means but it's a little firm and shifts extremely quick. Almost like my old fully built 60e without the harshness to go along with it
 

2004LB7

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Defuel typically refers to the fuel pulled out during a shift. this is needed to keep the transmission alive. you can put a lot of power through an Allison but if the defuel amount is incorrect then it can shorten it's life considerably. a good tuner should know how to properly set this up. when poorly tuned the transmission will have a hard time adapting to the power and could hang, flare, bang into gear, etc. smooth shifting is highly dependent on the defuel table
 

LSxBakakos

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May 29, 2022
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I just didn't know if you guys actually meant defueling or were mentioning the detorque. my previous file may have been non defueled shifts or not much of it. it shifted like a turbo 400 or like my old 60e. shift points were raised at part throttle which I didn't care for. We switched back to what I'd call a stock turbo max effort shift point. It's not harsh anymore, i wouldn't call it necessarily firm but it's a nice positive shift that's quick crisp with a tiny bit of firmness to it. The goerend couples quite firm though. The 4-5 at WOT for sure is defueled and I'm fine with that lol. Just out of respect for the guy I won't use his name but I use calibrated/Duramaxtuner so I'm sure it's within the right limits
 

LSxBakakos

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May 29, 2022
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Since I forgot to ask do I need to drop down the tunes and learn/go up from there? Or am I good to leave it where it's at? I tried attaching a video I took off snap but I've had zero luck uploading it to show you guys what it's doing
 

08lmm72mm

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May 13, 2019
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Best way to do it is putting on the biggest tune you'll use daily, do a fast learn, drive it. Then if you want to drop down to a lower level once and awhile it'll be fine
 

LSxBakakos

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May 29, 2022
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So I need to reset the taps again? I have 630mi on it since the new trans. Otherwise I take it I'll just have to be more patient since it's in probably in slow learn?
 

2004LB7

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Best way to do it is putting on the biggest tune you'll use daily, do a fast learn, drive it. Then if you want to drop down to a lower level once and awhile it'll be fine
that may help the trans from hurting itself but wont prevent the transmission from trying to adapt to the lower power then then again when you switch back to the higher tune. any time the throttle input doesn't match the MPH/RPM or power that the TCM is expecting the TCM will adjust it's adaptions to match

So I need to reset the taps again? I have 630mi on it since the new trans. Otherwise I take it I'll just have to be more patient since it's in probably in slow learn?
no need to reset. just leave it in whatever power level / tune you want to drive it in and keep it there as much as possible. let it adapt. then if you want to run a different tune then take it easy at first and let it adapt.
 

LSxBakakos

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May 29, 2022
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Illinois
that may help the trans from hurting itself but wont prevent the transmission from trying to adapt to the lower power then then again when you switch back to the higher tune. any time the throttle input doesn't match the MPH/RPM or power that the TCM is expecting the TCM will adjust it's adaptions to match


no need to reset. just leave it in whatever power level / tune you want to drive it in and keep it there as much as possible. let it adapt. then if you want to run a different tune then take it easy at first and let it adapt.
Thanks guys. I've kept it in 4, maybe I've gotta be more patient with it. It's still intermittently had the issue so I'll keep it there and just try letting it learn. I've realized 2nd gear roll will just blister the tires through 4th grab hard then do the little rev out deal. If im on a 3rd gear roll it'll break loose, hook then shift 4th and it's fine. Unsure if hard loads will "shock" an Allison into unlocking to keep itself from hurting but that's just me thinking out loud here