Freshly built 4l65e 2-3 flare
Thread Starter
Teching In
Joined: Aug 2023
Posts: 14
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From: Texas
One of the big issues with a number of shops is they simply dont have anyone who can look at the tune and understand what they are looking at. I would however try going into the tune of you have the capability and setting the shift time to 0,00 and see what happens. I use Tuner cat so may be different from what many have but in mine its under shift time vs tps and under line presure offset vs gear make sure no negative numbers there. Many times on the 2-3 the pcm is set to pull back presure to avoid a clunky feel ,
And a DYNO unless pretty high end is not the end all be all to making sure something works , A typical dyno can load to an extent, prove shifts and lockup andline presure and even then the person running it needs to know what they are looking at, In you case for instance assuming not a tuning issues which is could very well be. But if not this flare might only show as a Momentary slight unusual larger drop in line during the 2-3 shift but otherwise all work normally. You would have to know what you were looking for. Did you try the unplugging harness and doing the 2-3 shift manually ss I think I suggested earlier as that would tell us if it was indeeed a trans hydrulic issue if it still does it under those circumstances .
And a DYNO unless pretty high end is not the end all be all to making sure something works , A typical dyno can load to an extent, prove shifts and lockup andline presure and even then the person running it needs to know what they are looking at, In you case for instance assuming not a tuning issues which is could very well be. But if not this flare might only show as a Momentary slight unusual larger drop in line during the 2-3 shift but otherwise all work normally. You would have to know what you were looking for. Did you try the unplugging harness and doing the 2-3 shift manually ss I think I suggested earlier as that would tell us if it was indeeed a trans hydrulic issue if it still does it under those circumstances .
Last edited by Slowsilv; Aug 9, 2023 at 10:29 PM.
Thread Starter
Teching In
Joined: Aug 2023
Posts: 14
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From: Texas
It's more than likely in the tune. whenever you install a stall convertor, it needs to be retuned for that. Every trans i build with a stall convertor requires a custom tune. Surprised your CEL hasnt came on yet. Are you capable of tuning? If so, I can give you a list of things that need to be changed and what they need changing to. Or I can email you a tune file to compare.
you have tq management disable to zero. Yikes. That’s bad. Very bad. That’s what kills these transmissions. Whoever tuned it like that, probably should not be tuning. Copy what I have on mine for tq management, shift timing and pressures and then go try it. But never, ever disable tq management unless you just want it to break. Being that you are turboed, I’d probably add a few numbers to it. This is my sons NA table. My turbo car I have like 20 on the 1-2 and 15 on the 2-3 taken out.
Thread Starter
Teching In
Joined: Aug 2023
Posts: 14
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From: Texas
you have tq management disable to zero. Yikes. That’s bad. Very bad. That’s what kills these transmissions. Whoever tuned it like that, probably should not be tuning. Copy what I have on mine for tq management, shift timing and pressures and then go try it. But never, ever disable tq management unless you just want it to break. Being that you are turboed, I’d probably add a few numbers to it. This is my sons NA table. My turbo car I have like 20 on the 1-2 and 15 on the 2-3 taken out.
Thread Starter
Teching In
Joined: Aug 2023
Posts: 14
Likes: 1
From: Texas
you have tq management disable to zero. Yikes. That’s bad. Very bad. That’s what kills these transmissions. Whoever tuned it like that, probably should not be tuning. Copy what I have on mine for tq management, shift timing and pressures and then go try it. But never, ever disable tq management unless you just want it to break. Being that you are turboed, I’d probably add a few numbers to it. This is my sons NA table. My turbo car I have like 20 on the 1-2 and 15 on the 2-3 taken out.
I pulled the main trans plug and shifted 2-3 manually. It shifted perfect. After I put your numbers on my tune the trans shifts a lot better. But, it still jumps rpm on the 2-3 shift. Seems like the jump is quicker now, less sloppy. But still there. I guess next I need to test for a slow shift solenoid then if that is good swap the pcm for the other I have? I would have to license it so i would rather do that last
try upping the pressure a little more. And lowering the shift timing to 0.00 on the upper end.
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Joined: Mar 2023
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From: BERWICK PA
I actually have the shift timing on my Impala SS at 0.00 across the board. Factory the 2-3 had something like .500 for a 2-3 shift time. It shifts nice and not crazy harsh either I like it better that way after playing with it a while.
Of course it is an ALDL car 1995 , Also I had noted it factory had a line pull back on the 2-3 shift in all but the performance table which is not actually used in my car . Not sure where this would be and or if in HP TUNERS but fixing that really made the 2-3 feel more positive though did end up a little clunky feel at very light throttle but it is A PERFORMANCE Level 3 type build if I wanted smooth and easy I built the wrong build for it lol but it's still pleasant nice light bump at part throttle to very firm but not someone hit you in the *** shifts at WOT.
One thing I did learn sometimes the best way to solve a trans shifting issue when it's been tuned before is to back up to stock tune and start over 1 thing at a time. I helped a guy a while back and someone had the kickdown and upshift tables all crossed up I flashed it back to stock and sent it to him all was solved then told him what to change and how to set shift points, lockup and feel overall .
Again, however I have not messed a lot with OBD2 stuff yet only Tuner cat and my car mostly. I have looked at the HP TUNERS stuff and was able to help a few people some much of its similar. One day I'll get an OBD2 car or convert the Impala lol
Of course it is an ALDL car 1995 , Also I had noted it factory had a line pull back on the 2-3 shift in all but the performance table which is not actually used in my car . Not sure where this would be and or if in HP TUNERS but fixing that really made the 2-3 feel more positive though did end up a little clunky feel at very light throttle but it is A PERFORMANCE Level 3 type build if I wanted smooth and easy I built the wrong build for it lol but it's still pleasant nice light bump at part throttle to very firm but not someone hit you in the *** shifts at WOT.
One thing I did learn sometimes the best way to solve a trans shifting issue when it's been tuned before is to back up to stock tune and start over 1 thing at a time. I helped a guy a while back and someone had the kickdown and upshift tables all crossed up I flashed it back to stock and sent it to him all was solved then told him what to change and how to set shift points, lockup and feel overall .
Again, however I have not messed a lot with OBD2 stuff yet only Tuner cat and my car mostly. I have looked at the HP TUNERS stuff and was able to help a few people some much of its similar. One day I'll get an OBD2 car or convert the Impala lol
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Frank formerly of Performabuilt, Now just me, What can I build for you today? Call or message me. Click sig pic for my facebook
Frank formerly of Performabuilt, Now just me, What can I build for you today? Call or message me. Click sig pic for my facebook
Last edited by FranksCustomTrans; Aug 13, 2023 at 10:44 PM.
Thread Starter
Teching In
Joined: Aug 2023
Posts: 14
Likes: 1
From: Texas
Seems like anything I try isn’t helping at this point tune wise. My guess is something internal. Can’t be too bad the fluid is still pink. I don’t wanna open it myself just yet it could void the warranty. It is a RPM level VI for the people that asked. I’m not a newb to mechanics that’s my day job. However I have not built a transmission yet. I have one of my old ones in the garage ready to be put back together with a kit from Dana. It will be a spare for the one in the truck now. Later down the road when I figure out what is causing it I will post back
Sounds like there’s an internal leak. I just delivered a truck (2005 Silverado) and that trans shifts phenomenal. A leak a lot of people overlook is the input shaft. I leaned the best thing to do is press every one of them out the drum. Clean it up. And put a light scuff on the shaft and drum where they press together and then use loctite or permatex shaft retainer.
I built a transam unit a couple months ago for a kid who’s trans would burn up about every 30 days. Everyone want to blame the trans but the builder was to blame here. What did I find? I went to press the shaft out and it just fell out after my press moved it maybe a 1/16”.
they could have missed a bolt to be tightened on the valve body. Cut a lip seal. Not enough spring in the accumulator.
I built a transam unit a couple months ago for a kid who’s trans would burn up about every 30 days. Everyone want to blame the trans but the builder was to blame here. What did I find? I went to press the shaft out and it just fell out after my press moved it maybe a 1/16”.
they could have missed a bolt to be tightened on the valve body. Cut a lip seal. Not enough spring in the accumulator.
Last edited by Kfxguy; Aug 24, 2023 at 07:58 PM.