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t42 tcu

Big Ray

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is this what I need to make a 4l80-e work behind my 6.2l...?
 
Was hoping someone had an answer for you! I've got no input for stand alone tranny controllers, have you asked in the diesel section?
 
not yet...just doing research for future reference...
 
Ok, help me out here, whats a T42?

What about a part number? The ECM's all have part numbers, should be pretty easy to get that. I heard they are kind of pricey, but available.
 
My bad, should be TCM...it's a stand alone transmission control unit. module


I got the notion here...about mid-page...
 
Ignorance coming into play here, but can you use one of the diesel TCM's to do the same thing?

What's the T42 run? I will go on the high side and guess the GM TCM is going to run around $500, if available. I know the GM pieces must be available somewhere, AFAIK it's what the HMMWV's with 4L80E's use.
 
that's what I'm trying to find out...they're on ebay from time to time. there's a person selling them reflashed to your vin for $80...

I'm thinking [guessing] this might be what the 91 diesel burb used before engine computers...:dunno:


got to spend some time in the pick a part when it warms up some :whistle:
 
I suspect even the 1992+ trucks used them, until the diesels started to have things like the electric pumps or whatever. I know at some point they started to integrate into a PCM as well, just don't know what year. I'll see if I can find the GM part number for you. I know where one of these TCM's is sitting on a shelf.

Service number I got is 16196390. I didn't do ANY research to see what all this thing does, just that it controls a 4L80E. The wiring connectors look like the 1227165 ECM ones, and I'm sure others. Maybe the 1227747?

http://www.ebay.com/itm/REMANUFACTU...Parts_Accessories&hash=item43b6101495&vxp=mtr

About $100 cheaper than that here: gmpartsdirect.com they might kill you on shipping though, just have to plug in your address and see what they get you for.

As long as that is the right TCM, I would look into finding the ECM plugs for it, and going from there.

This shows that part number for '94-99 for some reason, and I'm pretty sure the 4L80E wiring changed at least once. I don't see the part number for the connectors though. http://parts.nalleygmc.com/showAssembly.aspx?ukey_assembly=393647&ukey_product=2819704
 
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Hopefully that gets you somewhere! Based on the other threads about the 4L80E, it sounds like there are only 11-13 wires to the trans? Maybe a few more here and there? either way, it wouldn't scare me to wire it up myself, just need to get the right pins (terminals) and TCM connectors, some wiring, and run it.

I would expect that there are enough 4L80E equipped trucks in the wrecking yard that wiring it up with the correct color wire from donor trucks is possible. *IF* you can find one the trans hasn't been removed/cut out of. :(

Guess you'd have to compare the cost of buying all the separate stuff, and the time of building it yourself, vs. the cost of an already done aftermarket setup.
 
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