When you removed the 8 pin connector and it did not manually shift, you determined for sure that the problem results from inside the transmission....You either have low Governor pressure or high throttle pressure..The only other possibility is a mechanical failure inside trans....Gov pressure can be checked at the port on passenger side of trans just in front of extension housing..Unit should have 0 at idle and increase with mph....If it does, you know that circuit is good and can check throttle pressure...You can check it by holding throttle wide open, unit should shift normally..if that is undesirable, attach pressure gauge in center port of transmission main case on passenger side...pressure should be about 60 psi at idle and increase with throttle position.....Throttle pressure problems are usually a result of debri finding its way into the throttle valve itself....


Goodluck !

 

I just drove the truck around the block again. First time through the gears it worked perfectly. However when I stopped and started forward again it went back to a 1-2 shift only and sluggish at that. It stayed that way.for the rest of the drive which was about 5 minutes. I think I'm gonna drop the pan, install a new filter and add completely new ATF4. I'm pretty sure jiffy lube didn't use AFT4 and I have a mix of their crap and ATF4 in there right now.

I need to read up on it but I guess adjusting my bands won't hurt while I'm in there either.

 

All righty then, just had a catastrophic failure of the transmission.

I took it for another spin around the block and this time while starting from a stop it moved forward about 10 feet then it felt like it popped out of gear followed by a metal on metal scraping sound. Like a power sander kind of whine/scraping sound. After that the truck wouldn't accelerate forward at all in any gear. I was right around the corner from home and some how managed to roll home. Reverse worked enough to get me in a parking space and that's it. My tranny is dead.

Anyone know where I can buy a new transmission in the Washington DC area?

 

Can you swap it out yourself? And, do you want a new one, or do you want to rebuild yours?

 

I doubt I could swap it myself. Never swapped a tranny before and I don't have the space to work on it. New/rebuild...honestly which ever is easiest and is going to give me trouble free driving.