I bought a 95 Explorer with a known bad transmission, rebuilt it (broken band and chipped intermediate apply piston), put it back in, and now it's acting odd.
It wants to start in third. I can manually start it in second (first rarely works), shift it to drive at about 30, and it's fine. It shifts into OD, locks the TC, and when given a bit of gas kicks down to second. It downshifts during deceleration, but once I come to a complete stop, it'll try to start in third again. The only transmission code it's giving is for incorrect first gear ratio, there is an off and on engine code for the EGR pressure sensor as well.
Does anyone have any insight on this problem?

 

These trans can have so many different issues and most of them are related to the valve body. It might be worth it to pull the pan down and move the shift solenoids around, if the problem changes then I would suspect one of the shift solenoids. If the problem is the same then I would look in the valvebody, like the 2-3 shift valve, misplaced keepers, valvebody gaskets, check *****, ect.

I found nothing about 3rd gear starts in my data base.

 

The keepers may well be an issue, one of the L retainers fell out and I think it's in the right spot but there isn't much info on where this one goes. Do you have a good picture of where those go?

 

This should be what you need, I think there are six "L" keepers

 

Ok, I got them all in the right spots, I'll just have to wait until I can drop the VB out again and see if any valves are stuck or damaged.

 

Well, a few months and a couple thousand miles down the highway, and it's fixed. The third gear start was likely some crud in the valve body, but it still was shifting really hard and had the OD off light flashing. After putting it into 4x4 low to move a trailer, it wouldn't come back out. As I investigated the issue, I found the transfer case plug was half undone, plugged it in and no more issues, not even a check engine light. The shifts are better too, still firmer than stock but not harsh like they were before. I'm actually really liking the shifts from this Trans-Go kit now, much better than the stock mush.