References for LS Swap Wiring

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Slooptin

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Can anyone point me in a good direction as far as wiring is concerned? I'm looking at picking up a Yukon Denali (6.2/6L80e, but I'm sure it will be similar for other combos) and I want to reuse the engine and trans for my swap, and from what I understand, as long as I retain the factory PCM/TCM, wiring is pretty straightforward? I'm assuming I'll need power for the starter and keyed power for the computers and probably some other stuff, but I'm not an electrical guru, so this stuff is foreign to me, but I'm willing to learn, just don't know where to look
 

TotalyHucked

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When I did my 5.3 swap, I wasn't able to save the Envoy harness so I used a PSI Conversion harness. I'm not a wiring guy either but managed to struggle through it with some help from some friends and my tuner. Check out the LS Swapped Square Body GM Truck page on Facebook and go to the "files" section. Tons of diagrams in there. Then if needed, just search the group, there's a bunch of good info/threads in there.
 

Bextreme04

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You are going to want to get a few things fixed on the 6l80 or try and get an 8l90 instead. I recommend some upgraded sonnex hard parts, like the 1-2-3-4 piston and the 4-5-6 drum as well as a billet torque converter. Those are the parts that are going to just blindly go out on you for no good reason. I had the converter go toes up on me while on a family vacation driving through Montana. No warning, just suddenly flashed trans temps up into the 350 degree range. It sends metal all through the trans when it fails too. Rebuilt it and just last Friday(2 years and 40k miles later) I was pulling out of a parking lot and slow acceleration up to about 10 mph and lost all forward gears. Turns out it cracked the 1-2-3-4 piston and now dumps all line pressure instead of applying the clutch pistons.
 

Camar068

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LT1Swap is a good start as well as all the sources and info mentioned above. What Bex is talking about is what threw my 6L80 "want" into neutral for a while (mainly the costs upgrading it).

LT1SWAP
 

Billydamnit

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Can anyone point me in a good direction as far as wiring is concerned? I'm looking at picking up a Yukon Denali (6.2/6L80e, but I'm sure it will be similar for other combos) and I want to reuse the engine and trans for my swap, and from what I understand, as long as I retain the factory PCM/TCM, wiring is pretty straightforward? I'm assuming I'll need power for the starter and keyed power for the computers and probably some other stuff, but I'm not an electrical guru, so this stuff is foreign to me, but I'm willing to learn, just don't know where to look
The person giving you advice on the 6L80, is dead on. At the very least, get a new converter. You do not want to have this trans rebuilt.
 

Slooptin

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Thanks for the advice, the Denali had a messed up 6L80. Owner didn't know much about it, but I'm glad I dodged a bullet there.

Appreciate the references guys
 

Bextreme04

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Thanks for the advice, the Denali had a messed up 6L80. Owner didn't know much about it, but I'm glad I dodged a bullet there.

Appreciate the references guys
The 6L80 is pricey to rebuild and has some weak points. I would highly recommend getting a combo with a 4L80. It’s easier to control and parts are MUCH cheaper. Here’s a pic of the cracked $40 part that left me stranded.
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While I was at it, I bought a $1000 billet multi-disk torque converter to replace the stock reman unit that I bought for the first unplanned rebuild, since we will be towing much heavier loads now with it. Between the torque converter, true-cool 40k cooler, and 4.10 gears… it pulls much better now. Basically stock rebuild parts for the 6L80 were $1500 when it blew up 2 years ago, plus another $250 for a stock converter. That makes it $2500 if you get an upgraded converter, and do the rebuild yourself. I bought upgraded rebuild stuff for my 4L80 that is going in my square for $700… and a stock torque converter is plenty beefy enough for a big block and regular towing.
 

TotalyHucked

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I definitely envy the guys with the 6/8/10 speed trucks but I'm honestly glad I went with the 65E. Simpler, parts are cheaper and less random failures. And I like the ratios better than an 80. Eventually I'll end up with a stick in it though
 

TPISly-C10

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i use and redone all the wiring from the donor my self.. cost $0 and work weel! :)
 

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