07 tahoe ly6 swap and 6l80

[iamdub]

Definitely open to input I was under the impression this had been done before. Is there a better option for a trans to handle the power and trq? I plan to run the 5.3 heads on the ly6 for better low and mid range and what they call the sloppy stg 2 cam. My understanding is this set up should be somewhere in the 500/500 range at the crank. I've heard many horror stories about the 4l60 when it comes to power but I'm open to building it and throwing in gears

As someone that has pined for more gears long before getting my Tahoe, I'd say to get a built 4L60. If you have enough power, the need for more gears is less. I've researched a 5- and 6-speed manual swap and, as much I'd like to have that, I'd likely end up with a 6L80 swap long before going manual. The TCM is built into the 6L80 instead of into the PCM like how your stock one is. You can make (maybe even buy at this point) an adapter harness to break the trans circuits out of the PCM harness and route them to the 6L80. You can put a block in the detents of your existing shifter linkage so that it only goes down one click below "D" instead of going down to "3", "2", and "1". You can swap in the appropriate shifter with the tap up/tap down rocker switch, but getting them to work is the hurdle. IIRC, it's something with the way it all communicates through the BCM. I'm not sure what all is needed for the appropriate gauge cluster to work, either. You need the one with the "PRNDM" display. You could do without the manual controls and cluster, though.

I want it to function 100% like factory and having manual control of the gears (TU/TD) is a must. My plans for such a swap would be to buy all the necessary parts from a wrecked '09+ and swap it into mine. I'd get the trans, cluster, shifter, harness(s), BCM and any other hard parts I may need (driveshaft, cross member or mod my stock one, etc.). I can handle the tuning myself. Sorta.

 

[ohio5pt3]

Thanks for the info I looked into the built 4l60 looks like I'd go the middle road. Its like 5k. I'm really wondering if I couldn't get that 6l80 in there cheaper.

 

[CaptainAmerica1]

Yes you can

 

[swathdiver]

I found a low miles ly6 and 6l80 combo for a great price. My tahoe is 2wd the truck is 4wd will that trans still work? Any input as to rather the 6l80 is worth it?

There is no LY6, 6L80 combo that I am aware of. The LY6 was used in 2500 and 3500 chassis and is always paired with the 6L90 transmission or 4L80. You would have to replace parts inside the transmission to make it physically work in your truck, along with a custom mount. These are the least of your problems, the 6L90 will require quite a bit of work to make it function correctly in your vehicle. The 2007 2500s with the LY6 ran the 4L80 transmission and paired up with the 6L90 in 2008. So I reckon you'd want a 2008 computer system, or yours converted to such.

 

[91RS]

It can be done but just isn’t worth it. The same money you’ll spend getting this done will buy you an Escalade or Denali after you sell your Tahoe. Then you also get all the other upgrades those trucks have over a Tahoe, plus the better rear end. And the work is already done, no engine swap, no aftermarket harness needed, no custom drive shaft, no disassembling a 4WD trans to swap parts to make it 2WD.