LQ4 with 4L60
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Teching In
Joined: Jan 2023
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LQ4 with 4L60 I'm currently installing a LQ4 with stage 2 cam in a Cherokee (XJ). I wanted to install a NV3500 as I ran the engine with a NV4500, so it already has a clutch/flywheel on it. However, this would require major firewall mods to move the powertrain back enough to get the shifter out from under the dash. Next option is a 4L60 that I have ungraded to 4L65. This leads to my main question, what harness and PCM mods will be required to run the 4L60 vs the 4L80 that came with the original engine? Or should I just start searching
for a 4L80? I'm not going to beat on it, so I would think the upgraded 4L60 would be OK. Thanks
for a 4L80? I'm not going to beat on it, so I would think the upgraded 4L60 would be OK. Thanks
Joined: Apr 2006
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From: Grand Rapids, Michigan
Cool that you're doing an LS swap on an XJ. My son has an XJ, but it's rusty as hell. We're looking for a rust free one to do an LS swap on. To answer your question, your PCM would need to be reflashed to control the 4L60E, and you'd need an adapter harness if you're using the harness from the donor truck. But it should be a relatively simple swap. XJs are fairly light, so a 4L60E should hold up, but I'd be more concerned with tire size and gearing in regards to longevity. You say you're not going to beat on it, so I'll assume you won't need the 4L80E.
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Joined: Aug 2018
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I'm currently installing a LQ4 with stage 2 cam in a Cherokee (XJ). I wanted to install a NV3500 as I ran the engine with a NV4500, so it already has a clutch/flywheel on it. However, this would require major firewall mods to move the powertrain back enough to get the shifter out from under the dash. Next option is a 4L60 that I have ungraded to 4L65.
This leads to my main question, what harness and PCM mods will be required to run the 4L60 vs the 4L80 that came with the original engine? There's different ways to do it:
1.) repinning the transmission case connector and adding the second speed sensor back to the ECU is cheapest. Not too bad. Look here: https://lt1swap.com/4l60e_4l80e_harness.htm
2.) Using an adapter at the case takes care of repinning there. Still need to add the second speed sensor back to the ECU. This kit has both: https://www.amazon.com/4L60e-4L80e-T.../dp/B076QLN4XR
In both cases, you need the ECU reflashed for the correct transmission. Make sure you give them tire size and gear ratio so your speedo is calibrated. Since you have 4x4, the second speed sensor is going to be in the transfer case in an OEM application; not sure how to applies to your TC.
Or should I just start searching for a 4L80? I'm not going to beat on it, so I would think the upgraded 4L60 would be OK. 4L60/65e should be okay.
Thanks
This leads to my main question, what harness and PCM mods will be required to run the 4L60 vs the 4L80 that came with the original engine? There's different ways to do it:
1.) repinning the transmission case connector and adding the second speed sensor back to the ECU is cheapest. Not too bad. Look here: https://lt1swap.com/4l60e_4l80e_harness.htm
2.) Using an adapter at the case takes care of repinning there. Still need to add the second speed sensor back to the ECU. This kit has both: https://www.amazon.com/4L60e-4L80e-T.../dp/B076QLN4XR
In both cases, you need the ECU reflashed for the correct transmission. Make sure you give them tire size and gear ratio so your speedo is calibrated. Since you have 4x4, the second speed sensor is going to be in the transfer case in an OEM application; not sure how to applies to your TC.
Or should I just start searching for a 4L80? I'm not going to beat on it, so I would think the upgraded 4L60 would be OK. 4L60/65e should be okay.
Thanks
Last edited by strutaeng; Jan 3, 2023 at 10:16 AM. Reason: additional information.
TECH Junkie
Joined: Jun 2008
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From: Nitro Alley
If you have a "Long Crankshaft" LQ4 Engine...
You will not be able to directly swap a 4L60E from a Gen-III/ IV SBC.
You could use one from a Gen-I or Gen-II Engine.
...Or have a custom Torque-Converter made.
You will not be able to directly swap a 4L60E from a Gen-III/ IV SBC.
You could use one from a Gen-I or Gen-II Engine.
...Or have a custom Torque-Converter made.
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Joined: Dec 2012
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From: Iowa
