trans not going into 4th gear even though log says it is?

[SimpleManLance]

well i just figured out that my truck hasn't been going into 4th gear at all. It will do 3rd gear tcc locked but that's it. i hooked the scan tool up today and checked it. it says it is in 4th gear and the tcc is locked but if i manually shift it to 3rd the tcc unlocks then locks again and the rpms go back to what they were before.

truck is a 2005 ccsb z71 sierra 5.3, 3.42, 32" tall tires. The only thing done to the truck is a built trans, trailblazer torque converter, and a k&n intake. I've only done trans tuning.. Could the tb stall be causing the truck to not go into 4th gear? I loaded the stock tune back in and it still wont go into 4th gear.

here is the current tune on the truck.