4l80 to 4l60 harness
PCM LOCATION TO TRANS LOCATION: C1-blue, C2-green
4L60E
C2-42 to T
C2-2 to U
C1-79 to S
C2-47 to B
C2-48 to A
4L80E
You’ll see that A & B at trans ARE THE SAME as 4L60E trans.
So, to make 4L80E harness work for 4L60E:
Move S at trans PLUG to location U
You need to account for T and S. The 4L80E had an INPUT speed sensor, NOT used on 4L60E, add two additional pins to TRANS plug at T and S.
Then you need to move the input speed sensor wires AT THE PCM to the correct location.
T at trans goes to C2-42
S at trans goes to C1-79
I made a google doc that explains the changes needed.
https://docs.google.com/spreadsheet/...hl=en_US#gid=0


