'97 C1500 4L60E to 4L80E Swap

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stutaeng

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@stutaeng Was looking into an 80e swap, but the only one in my area I could find that was the year I wanted was under a 3/4 ton 6.5 plow truck that rolled into the garage I work at lol.

Was really tempted to ask the guy how much he'd want for it. Woulda gotten a 14 bolt rear end from her too. Got that 4l60e for a steal though and I'm not gonna be making insane numbers with that 350 so :shrug:
The 4L80e transmission you are looking needs to be a specific year? I think any 93'+ will work. I think the 91-92 have do slightly different valve bodies and wiring harness, but after that year, they should all work.

Edit:
91-96 are pretty much the same mechanically, minus what I mentioned above. Change the short shift shaft to the longer one for the NSS.
97 is when the "rear lube" system got introduced. One of the cooler fittings is towards the back and it has a unique fitting that reaches into the center support.
late 99 is when they started putting the top LS bellhousing bolt
01 they made a change on the forward drum sprag or roller, can't remember what it's called.

For a swap, all you need to know if it's a front-lube or rear-lube for your cooler lines.
 
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Jesse_Wenting

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I think any 93'+ will work
Ideally I'd like a 98 just cause the truck is a 98, but the only one I could find in my area was a 91, and it was literally just the bare case. Didn't even come with the valve body. All of the yards around me pull parts for you cause of insurance or wtf ever :rolleyes: so I can't just walk around and look for what I need as easily as I'd like
 

df2x4

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^ That, pretty much.

If anything I lost a little in terms of acceleration from a dead stop, but I actually like overdrive of the 4L80E much better in this truck. The 4L60E wanted to downshift a lot on the highway with any slight incline, the 4L80E doesn't do that nearly as much as the RPM in OD is slightly higher.
 

L31MaxExpress

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My L31 van seemed to run better all around despite the taller 1st and 2nd gear. The stock converter is looser than the 60E converter and the engine was able to get into its powerband right away and stay there on the 1-2 shift.

This was with the 4L60E
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This was with the 4L85E.
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This was after Thorley Tri-Ys, I was actually reving it out 500 rpm less here.
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VIKING_MECHANIC

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Forgive me if I missed it in one of your posts, but why does your truck keep breaking 4L60E's? Anything very specific your after with the 80E?
 

df2x4

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Forgive me if I missed it in one of your posts, but why does your truck keep breaking 4L60E's?

Long story short, I had Black Bear Performance remove torque management from my tune (against their recommendations) and I also tend to beat on them on occasion. Those two things combined killed two 60Es in a very short period of time.

Anything very specific your after with the 80E?

Just less chance of catastrophic failure, and as a bonus it will hold the power if/when I ever get around to swapping in the LQ4 I have in the garage.
 

Supercharged111

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Forgive me if I missed it in one of your posts, but why does your truck keep breaking 4L60E's? Anything very specific your after with the 80E?

Let's just say he tends to bring out the weakness in things. I'll also say there are 2 kinds of 4L60s: those that have failed and those that will.
 
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