mini_mull
1/2 ton status
Would a 91 3/4 ton 4x4 burb have a 700R4 or a 4L80E? And what's the diff? Is the 4L comp controlled and a bigger pain to mess with, or are they about the same?
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
91 3/4 ton 4X4 has which OD tranny?
- Thread starter mini_mull
- Start date
mini_mull
1/2 ton status
OK, I found a post that mentioned the Light Duty had the 700R4, but they are rare, most are HD 8600 GVWR and had the 4L80E. But I am still wondering how much more complicated the install of a 4L80E would be than a 700R4, and if you swap engines and need a custom chip, is it more complicated and expensive because of the comp controlled 4L80E?
Hossbaby50
3/4 ton status
A 91 may have the 4L80E. Pray that it does. They are WAY superior to 700R4's. They are computer controlled but they run off a stand alone computer from what I have heard.
The 4L80E is alot stronger then a 700R4.
The 4L80E is alot stronger then a 700R4.
mini_mull
1/2 ton status
So the 4L80E comp is not connected to the ECM that runs the TBI?
What he said, it should be a 4l80e in the 91 3/4 ton, but it has a stand alone computer.
mini_mull
1/2 ton status
Great, thanks guys. Sounds like the perfect tranny, esp with the separate computer.
afroman006
1/2 ton status
I just tore apart a 91 dually with 454 and 4L80E and it only has one computer. Me thinks the engine and tranny puters work together.
OK, well maybe its not a seperate computer...but thats always what i had heard.
Either way though, that tranny kicks ass. Way better than the 700r4. So it doesnt' really matter how its controlled - you're lucky to be getting the one year of the old body style burb that came with that tranny.
Either way though, that tranny kicks ass. Way better than the 700r4. So it doesnt' really matter how its controlled - you're lucky to be getting the one year of the old body style burb that came with that tranny.
afroman006
1/2 ton status
Yes, I have one. Me sell it this summer though.
The first year for the 4L80E was 1991. If its in a gas engine truck it is run off of the same computer as the TBI system. If it's in a diesel engine truck its a seperate computer up until 1994. 94 and after the diesels computer controls the engine also. And by the way the I believe the 700r4 is a 4l60e by 1991 and they are also computer controlled.
The diesel stand alone computers are very hard to find - they run from 600 up. (1991-1993 only)
The gas engine 350/454 TBI/4L80E controllers (for a 3/4 or 1 ton) are pretty easy to get ahold of they run from 200 up. You need to verify the computer model number to make sure somebody is not just telling you it runs a 4l80e, they are different. (1991-1995) (research the internet) (Vortec engines also use the 4l80e from 1996 to present)
Aftermarket stand alone computers are pretty easy to find, but they run 900 and up to about 2000. You can find them used starting around 600.
And you still need to have a correct form VSS signal, a correct form engine speed/RPM signal and a correct form TPS (throttle position sensor) signal. Those are the minimum signals for any computer to run the 4l80e.
I have read methods of driving the 4l80e solenoids and TCC using only switched contacts. In theory it should work but I have never tried that route. I do have a spare 2wd 4l80e that I plan to try out a aftermarket TCI stand alone computer on as well as the manually switched method (someday project)
I have used the 454TBI/4l80e factory setup in a 79 K5 and it worked well. I am currently installing a 1992 6.5td/4l80e into a 78 suburban.
The diesel stand alone computers are very hard to find - they run from 600 up. (1991-1993 only)
The gas engine 350/454 TBI/4L80E controllers (for a 3/4 or 1 ton) are pretty easy to get ahold of they run from 200 up. You need to verify the computer model number to make sure somebody is not just telling you it runs a 4l80e, they are different. (1991-1995) (research the internet) (Vortec engines also use the 4l80e from 1996 to present)
Aftermarket stand alone computers are pretty easy to find, but they run 900 and up to about 2000. You can find them used starting around 600.
And you still need to have a correct form VSS signal, a correct form engine speed/RPM signal and a correct form TPS (throttle position sensor) signal. Those are the minimum signals for any computer to run the 4l80e.
I have read methods of driving the 4l80e solenoids and TCC using only switched contacts. In theory it should work but I have never tried that route. I do have a spare 2wd 4l80e that I plan to try out a aftermarket TCI stand alone computer on as well as the manually switched method (someday project)
I have used the 454TBI/4l80e factory setup in a 79 K5 and it worked well. I am currently installing a 1992 6.5td/4l80e into a 78 suburban.
Last edited:
