According to theory, the PCM won't shift the trans into O/D until trans fluid temp reaches 108 degrees. (F) If the temp sensor is lying to the PCM, that may be the cause of your issue......

That said, even on the coldest of days, my truck would shift into overdrive at right around 45 mph, regardless of how long I had been driving. (and, since I could hit 45 mph less than 200 feet from my driveway, I really don't think the trans temp was up to 108.....

I was afraid of that I'm trying to avoid everything dropping the pan and valve body I'm trying to eliminate all my other possibilities first I think my computer could be bad I'm gonna try a different computer tonight see if that changes anything and if that doesn't work I'm still at a standstill with this damn thing it would be different if it was doing it sporadically but the problem is so consistent it is weird

Can u give me more advice?
 

Do you have any other advice that may help my situation out so you mean tell me that locking in the torque converter didn't do any good other than dropping my RPMs like 200 because when I first hooked it up my truck was kicking in overdrive like it should around 45 to 55 and then it only worked like that for a day and then it went back to the same thing it will kick into overdrive but only at low speed's

That would suggest to me that you may have a bad connection at the PCM, however, if that were the case, it *should* set a code for it. Of course, I don't know if the trans codes would actually turn on the CEL. Really need to scan it for codes..... if you can get your hands on a scanner that reads data as well, watching trans temp might be enlightening too.

I'm trying to get power to my OBD every scan tool I've tried to hook onto it says error no connection

If you don't have one already, download the service manual for your truck from here. Wiring diagrams are in section 8W.

I'm going to pull the computer out of another truck and give it a shot and see if I have a bad connection to my PCM or if maybe my computer is bad I have another transmission that can go in the truck I'm not going to go through all that stuff until I know for a fact that it's not something stupid i'm beyond fed up with this whoever can give me the winning solution or turn me towards the right direction gets a free $50 bill

Hate bringing up an old thread, but has a solution been found to this issue? I started a thread but haven't had any luck with answers so far.

Has a solution been made for this issue?

I will tell you that this thread helped me fix this problem with my truck, (97 )
I have 2 switched on the dash, marked OD and TC Lock.
Now it all works and no CEL