Hey guys im working with a friend on a 4l60 to 4l80 swap on his 2005 4x4 rcsb sierra, we have everything we need so far from PATC:

#10T. You get the 4L80E to Tahoe 4L60E transfer case adapter, custom made 4L80E to 4L60E transfer case output shaft, 4L60E to 4L80E wiring adapters, LS1 motor to 4L80E crankshaft spacer and a #10C custom built 4L80E crossmember that moves the transmission mount to the correct position. You saw it here first. Even the best built 4L60E transmission in a heavy 4WD supercharged Tahoe wont last long, a built 4L80E transmission is twice as strong as a built 4L60E transmission. (We need the last 8 digits of your VIN number to insure you get the correct crossmember. Price may vary with model.) Cost $1234.00

4L80 transmission

LS type case

3200 Stall converter.

Now my only concern here are the front and rear driveshafts, are there any longer/shorter yokes we can use and still retain the stock shafts?

Thanks.

 

PATC uses a custom made 27 spline output shaft.

This is a poor design and has been proven time and time again to fail in high Horsepower situations.

I recommend you buy the correct input gear on the transfer case side that mates up to the 32 spline shaft on the 4L80E.

As far as the drive shaft, I don't believe so. Im sure its hard to find in your country but Custom is the way to go. I believe you can use a 2500 shaft in the front but the rear will need to be modified.

Good luck!