90ss 454 4l80e swap?

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brocks 97

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What would be required for a 95 or so year 4l80e transmission? I know the mechanical end of the swap but don't know what would be required wit electrical. I am pretty sure the ecm and harness from the done truck would be required but is thereally anything that would be required other than that?

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Brock
 

brocks 97

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Also what year of harness and ecm would be compatible with the 90 model?
 

GaryCCR

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I may be wrong but a 90 would have a 700r4. If you want to use the 4l80 you'll have to use a aftermarket computer controller to have it shift.

What year is the truck?
 

df2x4

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I'm doing an 80E swap into a '97 right now so I've been looking into this a little. I know '91 was the first year for the 4L80E. You might not even have to swap harnesses and PCMs. I'd contact http://tbichips.com/ or someone else reputable for tuning the older OBD1 computers and see if they can reprogram your existing chip to control an 80E. You might have to swap some wires around, and the 80E takes a different speed sensor.

If you do have to swap PCMs, (which is entirely possible, I know nothing about the old OBD1 stuff as both of my trucks are '97s) I know that the 96-99 Vortec era PCMs and harnesses can control an 80E with no issues. Or you could always do the 0411 swap from a GMT800.
 

brocks 97

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The truck is a factory 70k 1990 454ss with a 3 speed th400 and a 14 bolt rear in 91 they put the 4l80e in but it was not a very good tranny in the first year so the tranny I would want is from a 94-95 it has a bad engine and has been parked for over 15 years but I would love to have overdrive.
 

CRF450R

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The truck is a factory 70k 1990 454ss with a 3 speed th400 and a 14 bolt rear in 91 they put the 4l80e in but it was not a very good tranny in the first year so the tranny I would want is from a 94-95 it has a bad engine and has been parked for over 15 years but I would love to have overdrive.
Basically you can go what ever year or 4l80E you want but you will need a stand alone. Its nice to see someone wanting to ditch a pos TH 400 for a nice 4l80E 4spd OD you will definitely not regret it and will definitely ad value to the truck I'd love to own a 454 SS or even a 350Sport (they never ever made a 350SS)

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df2x4

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they put the 4l80e in but it was not a very good tranny in the first year so the tranny I would want is from a 94-95

Just to clarify, I wasn't implying that you should use a '91 80E. Just wanted to make the point that the factory PCM in your '90 might be capable of controlling it if you found the right tuner. Personally I'd go with a '97-'99 4L80E if possible, as they were the most updated of the 80Es while still retaining the old SBC/BBC bellhousing bolt pattern.

EDITED for content
 
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CRF450R

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Just to clarify, I wasn't implying that you should use a '91 80E. Just wanted to make the point that the factory PCM in your '90 might be capable of controlling it if you found the right tuner. Personally I'd go with a '97-'99 4L80E if possible, as they were the most updated of the 80Es while still retaining the old SBC/BBC bellhousing bolt pattern. Anything newer will have the LS bellhousing bolt pattern and won't work with a TBI or Vortec engine.



Like I mentioned above, you need to make sure you don't get one that's too new. Otherwise it won't bolt up to a TBI or Vortec engine in these trucks. '99 or below should be OK.

EDIT - Unless he's LS swapping the truck, in which case he'd want the opposite, 2000 or newer.
Um correct me if I'm wrong since 1957 gm has never changed there bell housing even on the ls engine. There was a blown duramax( was out of 07) sitting in the corner of my shop were I work and it's even got the same bell housing pattern as my 1994 5.7tbi.

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df2x4

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Um correct me if I'm wrong since 1957 gm has never changed there bell housing even on the ls engine. There was a blown duramax( was out of 07) sitting in the corner of my shop were I work and it's even got the same bell housing pattern as my 1994 5.7tbi.

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You're right, it wasn't much of a change. I'm actually editing my original post right now. The main difference is that there's an extra bolt at the top of the bellhousing on the LS engines, which you can just leave out with no negative effects. Any 80E should bolt up!
 

CRF450R

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You're right, it wasn't much of a change. I'm actually editing my original post right now. The main difference is that there's an extra bolt at the top of the bellhousing on the LS engines, which you can just leave out with no negative effects. Any 80E should bolt up!
I didn't know that now I know.

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