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Discussion Starter #1 (Edited)
I am new to this forum. I have installed a 4BT into a 97 H1 Hummer with the existing 4L80E tranny. I have installed a TPS sensor on the rotary pump, removed the electronic throttle pedal and installed a manual one, installed a crank position sensor and a grooved balancer pulley off of a 6BT. I was told that I could run the existing computer controlled transmission without an aftermarket controller if I wired these components into the system. Problem is I don't know for sure what imputs the computer needs from the engine to operate the tranny, or how to wire them. Has anyone done this, or attempted to do this? Thanks, Ron
 

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IIRC, 95 was the last year with a standalone controller for the trans, after that the engine computer also handled transmission duties. So.. I don't think the 97 controller is gonna let you do what you're wanting. And I've the feeling you're going to need a reprogram of the controller anyway to accommodate the differences between the engine that it had and the 4BT.

Please, anyone, if I'm wrong on this chime in!

You might want to be looking at a CompuShift aftermarket controller for it.
 

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Man, this has really been discussed lately, and at length.
Can't find the thread now, though.

Something about getting the TCU from a pre-94 truck with a mechanical 6.5T or up to '96 in the vans with the 6.5T?
 

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Man, this has really been discussed lately, and at length.
Can't find the thread now, though.

Something about getting the TCU from a pre-94 truck with a mechanical 6.5T or up to '96 in the vans with the 6.5T?
That's what my brain was coming up with..

I haven't found the recent one, but had some info in my old thread about it:

http://4btswaps.com/forum/showthread.php?t=1318

I think that most of the time the conclusion has been to get the aftermarket controller and don't look back.
 

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I think that most of the time the conclusion has been to get the aftermarket controller and don't look back.
Yeah, I did remember someone saying a lot of re-programming was needed with the factory TCU. I guess if you got the coin to play with a H1 you can surely find $1200 for the aftermarket controller.
 

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In '94 not only did GM go to an integrated TCU/PCM, but the actual electrical components in the 4L80E changed. The shift force motor on '95 or so and newer 4L80E's uses a different control frequency. From what I understand, you cannot use an early OEM controller with a late tranny or vice versa.

I'm working on a '97 6.5 K2500. I bought the TCI controller used off evilbay for a decent deal.
 
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