Same here, I paid a lot for the nice transmission rebuild, not worth it for the chirping of the big tires, haha.

No its a totally stock rebuild, the original transmission I had to drive 500 miles pouring in transmission fluid as fast as it squirted out to get it home to fix the leak. It lasted about 6 months before it quit, that when i had it rebuilt. With the stock tune you cant feel it shifting at all ...

I've just put the 87 Tune on my 02 Avalanche 2500. It has the 4L80E Transmission, it shifts a bit hard like I'm trying to chirp my tires. I went into custom settings and changed the partial throttle shift pressure down to lowest setting -25 and it didn't change anything. Am I doing something wrong ...