4l80 swap

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01-05-2021, 07:53 PM

Shawn87

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4l80 swap

Quote:

Originally Posted by nonnieselman

Edited: all info on this post..

Attachment 139809

How to swap wires.

Transmission connector:
Attachment 139810

Remove cover:
Attachment 139811
Attachment 139812

Remove white end:
Attachment 139813

Small knife works good to bend the lil grey clip back to remove the ends:
Attachment 139814

Put the white piece back on, the grey cover, and your finished, that easy.
Attachment 139815

After all that work,,, i think this 2004 harness is already a 80E harness

Attachment 139816

What about the 2008 newer body Chevy Silverado the tcm plug is totally different? What’s pin #s do pin into that year of truck for the iss wire?

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01-05-2021, 09:12 PM

1FastBrick

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Quote:

Originally Posted by Shawn87

What about the 2008 newer body Chevy Silverado the tcm plug is totally different? What’s pin #s do pin into that year of truck for the iss wire?

nonnieseleman hasn't been on here since 2013....

Wiring mods...
Remove K(orange), V(light blue), S(white), T(tan/black) and U(brown) wires from transmission connecter. Move U(brown) wire to the S location.
Front Input Speed Sensor (ISS) is made by using the orange and light blue wires. Add a VSS connector, connect orange to terminal A and light blue to terminal B. Move the low signal wire from pin 45 to location 26 in the TCM harness.
Install the front Input Speed Sensor wiring connection
Install the shift selector switch on the driver side you removed from the 60.
The factory speed sensor can plug back into the 80e tailshaft sensor

PCM/TCM...
Conversion is finished, had to get a 2008 Chevrolet Express 4.8L/4L80e van C2500 TCM tune to get the transmission to shift correctly. There was nothing special done to make the TCM work in the Silverado, just swap them out. The TCM was loaded with a factory tune for an 80e transmission.

Type: Chevy Express (V8) 2008
VIN: 1GCGG25C481106014

TCM...
Segment 1: 24239927
Segment 2: 24235887
Segment 3: 24251658
Segment 4: 24235883

Without the 80e TCM tune there was no speedo output to the PCM and the tune would not enrichen the fueling when accelerating.

Taken from here...
http://www.ls1truck.com/forums/power...on-gmt900.html

Last edited by 1FastBrick; 01-05-2021 at 09:23 PM.

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01-05-2021, 10:26 PM

Shawn87

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4l80 swap

1fastbrick
Sorry it won’t let me reply to the original message for some reason. But I already have my 45 pin moved the 26 on the TCM pin side I’m just not familiar with this year with the V. U. And S. coding on the plug?

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01-06-2021, 02:47 PM

1FastBrick

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You can't reply to it because I locked the thread. The person whom started that thread has not not been on since 2013. The plug orientation and pin location was on the very first page.

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