4l60e to 4l80e ?
4l60e to 4l80e ? I was reading the sticky about the 4l60e to 4l80e. It states that you need to add a plug for the input shaft speed sensor and repine the plug for the trans. That I under stand, What I don’t under stand is it also states that I need to repine the pcm connector. I know I need to reprogram but repine why? If so whitch pins and where to. Thanks for any help 
Last edited by 88s10; Mar 16, 2007 at 01:43 PM.
Joined: Sep 2004
Posts: 3,148
Likes: 12
From: Downers Grove, IL
The internal wiring harness for the 4l80e is different than the 4l60e. GM changed the locations of the pins on the connector.
Actually my theory is that the 4L80E uses the same pin locations as the LT1 4l60e, GM usually keeps things the same so I think they decided on the locations for the early (LT1) 4l60e and then they used those for the 4l80e. Then when they updated the 4l60e for the LS1 they just left the 4l80e wiring alone. None of this statement was based on facts, just gut feelings.
/ back to our regularly scheduled thread
Actually my theory is that the 4L80E uses the same pin locations as the LT1 4l60e, GM usually keeps things the same so I think they decided on the locations for the early (LT1) 4l60e and then they used those for the 4l80e. Then when they updated the 4l60e for the LS1 they just left the 4l80e wiring alone. None of this statement was based on facts, just gut feelings. / back to our regularly scheduled thread
TECH Resident
Joined: Dec 2004
Posts: 841
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From: Baltimore, MD.
Originally Posted by 88s10
I was reading the sticky about the 4l60e to 4l80e. It states that you need to add a plug for the input shaft speed sensor and repine the plug for the trans. That I under stand, What I don’t under stand is it also states that I need to repine the pcm connector. I know I need to reprogram but repine why? If so whitch pins and where to. Thanks for any help
I think the TCC lockup functionality is the same, so you don't have to move that at the PCM end.
However, the 60E doesn't have an Input Shaft Speed Sensor, and that's on a different set of pins on the PCM. And there just happens to be an extra pair of wires in the harness which can be used, but start and end at the wrong spots. I think the extra wires are for a shift solenoid that the 80E doesn't have / use.
The nice thing about the swap from the 60E to the 80E is there are the correct number of wires in the harness already. Wouldn't it be fun if you had to add 2 wires to the bundle, from PCM all the way to the trans. What a pain in the @$$ that'd be, especially with everything in the car / truck. It is a bit annoying that they're busy moving wires / pins around, but it could be worse.
'JustDreamin'
