Good afternoon everybody, been looking around and can't seem to find anybody having this same issue. I have a 99 F250 with a 7.3, 4WD and a 4R100 auto trans TS 6 pos chip, 4 in turbo back exhaust, and spectre cold air intake. Now to the point. Replaced my tranny with a rebuilt 4r100 drove it home from my buddies house no issues, since then it seems it will shift into neutral while driving down the road whenever it feels like it. Pretty much replaced the entire brake system in this truck short of sensors and lines. Replaced steering gear box, and I think that's about what I've done so far. My question....is there a sensor or something that could cause this, I've replaced the neutral safety switch and checked 100 times that everything is hooked up properly and I know before the trans it seemed when I hit the brakes it would seem to come out of gear, that is why I'm asking about sensors. Otherwise I'm still under warranty and have to yank the tranny again. Please help and thank you in advance.