Ford Transmission :: 2001 7.3 - Half Shift Between 1st And 2nd - Stuck In Gears?

2 wheel drive. No problems shifting until a few weeks ago when I put a chip in the truck. Then became a funny sort of half shift in between 1st and 2nd. Kind of a half shift and then a final hard shift into the next gear.

I have only driven the truck with the chip setting in economy by Gearhead which is 40hp. Well, all day driving in an economy but I have played hard with all the settings, smoking my tires and what not but never actually driven it into anything other than the economy.

Tonight it's done. Starting in the normal drive from a red light it was in between that funny shift and then it just fell back all the way with a hard thunk followed by it wouldn't shift at all out of first gear. Took it out of tunes, same difference. Found out when I take off in drive it won't shift on its own out of first but when I put it in second from the tree it shifts into second as normal, coming from the drive. Then when I start getting up into the rpm range that she normally should shift past second I put her back in drive and she shifts into third (and fourth?) normally. If I remove the overdrive it still immediately downshifts. When I turn it back on it shifts back up normally.

But again, starting from drive I have to put it into second and then into drive for it to shift. I still have reverse and it still kicks directly into first from the park and takes off, just doesn't shift from first to second on it's own.

I checked the tranny fluid, it's seemingly fine. Great red color and full. Does not smell burnt at all. No flashing light or anything anywhere either. No blinking on the overdrive light on the stick or no warning lights anywhere else.