Stalemate with my trans

[Tivs]

I have a 99.5 with a 4r100. It seems to shift early sometimes from 2nd to 3rd (what it feels like) super early causing me to lose power specially at WOT or pulling a trailer....but the other half of the time it pulls hard and no issues. It also sounds like the turbo is dumping too soon ( i have no gauge) when it shifts funny. I have a new alternator which fixed the rough shifting (Still shifts firmer than any other 7.3 ive been in) I DONT have a chip or anything but i am straight piped...could what im feeling be a surge or something due to lack of back pressure? Ive heard two things that could fix it: 3rd brake light (which i disconnected and it felt like it stayed in gear longer) or EBPV sensor. or could it be my TCC locking causing my truck to feel like shifting and its actually "Stalling". I also have NO codes. Or is what im feeling is the turbo dumping causing the truck to lose power causing the truck to shift to compensate.

[Colotow]

I'm rebuilding my wife's tranny, and in the ATSG manual, it says that a blown brake or 3rd brake light can affect the shifting on some automatics, and that LED tailights can trick it into thinking it has a blown bulb. This affects the torque converter clutch engagement at 30% throttle or less

I just got in the resistors from superbrightleds.com and need to install then on hers.