4th gear will not engage

[Atomic]

I have a 2004 silverado with the 4l60e and a PI 2600 triple disc stall.
I just had my trans rebuilt a few thousand miles ago when the 2-3 band burned up because I lost fluid without knowing it (cooler had a crack). Since then it has worked fine until now.

Problem is it will not shift into 4th until about 50 (regardless of what I have 3->4 set to), and even then it will downshift to 3rd with any application of throttle. It will only hold gear if im going about 65+. The TC will only lock in 4th and stay locked past 60mph.

Ive checked the fluid level and it is fine, fluid is still red doesnt look burnt or smell burnt. I havent dropped the pan yet.

I am thinking either the 4th apply servo is cracked or the 3-4 band is burned up.

I attached my tune, scanner cfg, and log file. Notice the hunting between 3 and 4 at speeds <60.

thanks for any help

[Russ K]

That's because your 4-3 shift speed is higher than the 3-4 shift speed.

Russ Kemp

[Atomic]

haha, wow do I feel like a noob right now...

thanks