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Old 07-09-2019, 06:30 PM   #1
72jimmy4x4
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Ls swap transmission question

Most of the swaps that I see are 4L80 trans.
I plan and have a 6L90E to use. Jimmy is a 4x4
What is the reason that most are using the 4L80?
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Old 07-09-2019, 07:19 PM   #2
p0508
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Re: Ls swap transmission question

There are way more available 4L series transmissions, both the 60 and the 80 available in junk yards. They are much less expensive to buy, build, and tune.

Honestly for sheer simplicity, cost, availability and longevity I would prefer a built 4L60/80 over any 6L.

You will probably struggle to figure out a way to control the 6L90e and you will need a Gen4 and up LS.

Built 4L60E: Cheap, simple, you can have a built one rated for 600hp/tq with a converter for 1200-1400 bux to your door.

Stock/Built 4L80E: Overkill for most people, unless you plan on making big power

6L series: Hard to tune, control without factory Gen 4 and up entire drivetrain including PCM and Harness. wont hold as much power as built 4L, less common, way more $$$$$$$$$$$$$

Not saying it can't be done, or hasn't been done, and if you want it done you can do it, just more cons than pros to the average swapper, but you already have a 6L90e, I say go for it.

Last edited by p0508; 07-09-2019 at 07:32 PM.
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Old 07-09-2019, 08:02 PM   #3
57taskforce
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Re: Ls swap transmission question

Quote:
Originally Posted by p0508 View Post
There are way more available 4L series transmissions, both the 60 and the 80 available in junk yards. They are much less expensive to buy, build, and tune.

Honestly for sheer simplicity, cost, availability and longevity I would prefer a built 4L60/80 over any 6L.

You will probably struggle to figure out a way to control the 6L90e and you will need a Gen4 and up LS.

Built 4L60E: Cheap, simple, you can have a built one rated for 600hp/tq with a converter for 1200-1400 bux to your door.

Stock/Built 4L80E: Overkill for most people, unless you plan on making big power

6L series: Hard to tune, control without factory Gen 4 and up entire drivetrain including PCM and Harness. wont hold as much power as built 4L, less common, way more $$$$$$$$$$$$$

Not saying it can't be done, or hasn't been done, and if you want it done you can do it, just more cons than pros to the average swapper, but you already have a 6L90e, I say go for it.
Guess that’s why the 6l80s in stock form will run to about 700 hp in the 5th gen Camaros? The 4l80 won’t do that stock sorry. I’ve got a 4l80e in my Silverado and its been an awesome tranny don’t get me wrong, it’s done everything I’ve needed for 200,000 miles. That said the 6ls are really good performers. 1st and second are geared way deeper and get you out of the hole so much better than the 4 speeds. I’ve got a 6l90 for my K20. I’m contemplating running it behind my ly6 6.0 gen 4. It can be done in our trucks, it will cost more to do though.
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Old 07-09-2019, 08:16 PM   #4
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Re: Ls swap transmission question

A built 4L80e will hold more power, more reliably and easier than a built 6L anything.

I've been down the 6L road twice with 690rwhp silverado and a 880 rwhp C6.

They are a pain to tune, a pain to build and are more expensive, period.

There is a reason only about 2 companies (circle D and Century Transmissions) off the top of my head that touch them. The rest (gearstar, rpm, etc etc) big horsepower trans builders don't touch them. $6500 dollars later..........

Last edited by p0508; 07-09-2019 at 08:26 PM.
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Old 07-09-2019, 10:10 PM   #5
72jimmy4x4
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Re: Ls swap transmission question

I do have the matching 6.0 LY6 still bolted together.came with everything, harness, ECM, pedal, rad , coolers and every thing on the front of the engine. Has 60 000 miles, donor truck was hit from the back.
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Old 07-09-2019, 10:38 PM   #6
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Re: Ls swap transmission question

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I do have the matching 6.0 LY6 still bolted together.came with everything, harness, ECM, pedal, rad , coolers and every thing on the front of the engine. Has 60 000 miles, donor truck was hit from the back.
Your set then, advance adaptors makes a kit to run an np205 behind them FYI. I’m still saving for the Maggie supercharger and gpi ss1 cam for my truck. That’s happening after the twins on my Camaro though.
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Old 07-22-2019, 11:00 AM   #7
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Re: Ls swap transmission question

I have a 6L90 behind my L96 Gen IV. Still working through the swap but mine came with the engine/donor vehicle so I'm making it work. I just finished the NP205 rebuild with the adapter and it was straightforward.
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Old 08-11-2019, 08:42 AM   #8
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Re: Ls swap transmission question

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I have a 6L90 behind my L96 Gen IV. Still working through the swap but mine came with the engine/donor vehicle so I'm making it work. I just finished the NP205 rebuild with the adapter and it was straightforward.
Can you provide pics of the 6L90 with the NP205 Transfer case Thanks !!
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Old 08-15-2019, 03:05 AM   #9
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Re: Ls swap transmission question

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Can you provide pics of the 6L90 with the NP205 Transfer case Thanks !!
The final drive on the 6L80/99E is the same as the 4L60/70/75E more **** to break
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