4L80 swap question

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#1taho

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inhave been researching the 4L80
Swap in my taho to make it a more reliable and better tow vehicle.
The one question I can’t find the answer is what year tranny can I use ?
For anyone else doing this
-the transfer case in a taho is 27 splind input shaft and the 4L80 is 32 splined. The transfer case can be a direct swap from a 4 button 2500 Silverado.
- a grind drive shaft from a 2500 duramax 4x4 Allison tranny should be a direct fit.

I will confirm this when I get the swap completed.

If anyone who has do the swap can add some pointers please chime in.

I have a guy to do the drive shaft. And a guy to change out the input shaft on the transfer case if I can’t find one out of a 2500. My tunner said he can pre tune my spare computer with my tune and the factory 4L80 tune. Then drive it there for a better tune. I will do the cross member my self and I will add and move the wires myself.
I feel I am missing something!!!
 

6speedblazer

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i would try and stay 97 and newer on the 4l80e as thats when they changed the cooler port locations.
 

bottomline2000

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Man I somehow missed your pm. To answer your question, yes I got the bugs worked out. Turns out it was all tune related. It seems the only way to have a proper shifting 4l80 using black bear is to run the 4160 tune with relay harness instead of the 2 separate harnesses with a 80e segment swap.

If your tuner is using hp tuners you do the pin swap and the vss sensor like a proper 4l80 segment swap. If he using efi live you are going to have a fight to get the tune to work right in O/D. I'm running a stock 4l80 tune and mine shifts great as far as feel around town smoothness and crisp tight shifts at full throttle.

I'm 2wd so I can't help on the transfer case part. I added a transgo shift kit to mine and there are some specifics you don't want to do from their kit like drill your valvebody. I can give you some direction on this depending on what u are doing. The purpose of this kit is to dual feed the clutches and give the trans it's infamous holding power, not just make it bang gears.

Hope I'm not too late for the party!

Sent from my SAMSUNG-SM-T377A using Tapatalk
 
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rockola1971

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Im not sure why everyone believes they have to go get a donor driveshaft instead of just having a new one made. Its not very expensive at all. I had to have one made for my Sierra Z71 back in 2006 or so and it was like $200 with new ujoints. And the custom made one was stronger than oem. Granted the shop was local so I didnt have to pay for shipping to me but if you ask around at one of your local semi repair shops they can point you to where to get a new driveshaft made locally.
It is true that the 4l60e and the 4l80e have different OUTPUT shafts.
 

6speedblazer

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Man I somehow missed your pm. To answer your question, yes I got the bugs worked out. Turns out it was all tune related. It seems the only way to have a proper shifting 4l80 using black bear is to run the 4160 tune with relay harness instead of the 2 separate harnesses with a 80e segment swap.

If your tuner is using hp tuners you do the pin swap and the vss sensor like a proper 4l80 segment swap. If he using efi live you are going to have a fight to get the tune to work right in O/D. I'm running a stock 4l80 tune and mine shifts great as far as feel around town smoothness and crisp tight shifts at full throttle.

I'm 2wd so I can't help on the transfer case part. I added a transgo shift kit to mine and there are some specifics you don't want to do from their kit like drill your valvebody. I can give you some direction on this depending on what u are doing. The purpose of this kit is to dual feed the clutches and give the trans it's infamous holding power, not just make it bang gears.

Hope I'm not too late for the party!

Sent from my SAMSUNG-SM-T377A using Tapatalk

why did justin keep trying to do a 4l80e segment swap and not find a tune that has a native 4l80e section? segment swaps are most common in platforms that didnt get a factory 4l80e, 4th gen f-body is a great example. in the GMT800 platform he easily could have found a 6.0/80e combo then tuned the engine side accordingly.

i only bring this up, because i have had nothing but issues with segment swaps. of the handful i have tried, i dont think i have had a single one work 100% correct. granted this was on hptuners 2.25 beta. so it was a few years ago. But i had so many issues with the ones i tried, i now just turn those tuning jobs away as i cannot guarantee a favorable outcome.
 
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bottomline2000

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why did justin keep trying to do a 4l80e segment swap and not find a tune that has a native 4l80e section? segment swaps are most common in platforms that didnt get a factory 4l80e, 4th gen f-body is a great example. in the GMT800 platform he easily could have found a 6.0/80e combo then tuned the engine side accordingly.

i only bring this up, because i have had nothing but issues with segment swaps. of the handful i have tried, i dont think i have had a single one work 100% correct. granted this was on hptuners 2.25 beta. so it was a few years ago. But i had so many issues with the ones i tried, i now just turn those tuning jobs away as i cannot guarantee a favorable outcome.
That's a good question and I have no idea. I basically have a HD drivetrain so you would think that would be the ez route. I just found put the remaining issues I have are not native to a stock HD tuning. The only good thing is at full throttle I don't have the issues.

My truck shifts like this: first, second, third, third lock converter, forth locked converter, unlock to 3rd, 4th locked converter..keep constant throttle application or it unlocks to 3rd, rinse and repeat...I know the 3-4 issue is tune related but because of the 0 throttle input being a efi live issue I just left it as is for now.

Hptuners can now do a proper segment swap which would be my next step, but it means having my truck completely retuned and hoping for the best.

Sent from my SAMSUNG-SM-T377A using Tapatalk
 

yukon702

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Man I somehow missed your pm. To answer your question, yes I got the bugs worked out. Turns out it was all tune related. It seems the only way to have a proper shifting 4l80 using black bear is to run the 4160 tune with relay harness instead of the 2 separate harnesses with a 80e segment swap.

If your tuner is using hp tuners you do the pin swap and the vss sensor like a proper 4l80 segment swap. If he using efi live you are going to have a fight to get the tune to work right in O/D. I'm running a stock 4l80 tune and mine shifts great as far as feel around town smoothness and crisp tight shifts at full throttle.

I'm 2wd so I can't help on the transfer case part. I added a transgo shift kit to mine and there are some specifics you don't want to do from their kit like drill your valvebody. I can give you some direction on this depending on what u are doing. The purpose of this kit is to dual feed the clutches and give the trans it's infamous holding power, not just make it bang gears.

Hope I'm not too late for the party!

Sent from my SAMSUNG-SM-T377A using Tapatalk

What year is the 4l80 you put in your ride? I'm going to be doing this swap as well. I read the best 4l80s to install were from 2002 and up, true?
 

bottomline2000

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What year is the 4l80 you put in your ride? I'm going to be doing this swap as well. I read the best 4l80s to install were from 2002 and up, true?

I have a 2008 4l80..its actually a 4l85 because of the 5 planetary gears, but most people say this isn't a weak link for the 80e anyway. I've seen some builders like Jakes prefer the older cases but he does a lot of custom touches to his, but I like having the split cooling lines on the newer cases. There are some issues that may be exposed after the 7-800hp mark, but as of now my cammed 6.0 doesn't seem to make my trans break a sweat..I would recommend a reprogram kit or dual feeding the trans to get the full holding potential out of it.
 

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