Did you ever figure out what it was man? Was it a selenoid?

 

.....

 

Hey, sorry I can't be more specific at the moment but there is a solenoid on the valve body that supplies the converter lock up if i remember correctly If your laying under the truck head towards the front of the truck there is a solenoid that will be on your left side front of the valve body. That is the Converter clutch FWM solenoid . You can test it either by using a jjumper and supply voltage or by reading the resistance across the terminals. According to the drawing it should read between 10-15 ohms. If it reads and/or test good then you may have an electrical connector problem or a stuck spool valve . The converter clutch regulator valve is located next to it. If you feel froggy you can jump in there and get a solenoid kit and a rebuild kit and rebuild the valve body. Another option is to pull the valve body off you could just remove that particular valve and inspect it for trash in there causing it to hang up or if there is any scoring on the spool valve itself causing it to hang up. If you have never dissembled a valve body make sure you have a good diagram and how to list as there are little ***** in there that if you lose one or put it in the wrong place you will pull your hair out trying to find your problem. You could also see what a trans shop would charge to check your pressures also. Option next is order a rebuilt valve body and install it. Really that would be the fastest and easiest way and they aren't that expensive. Here is a link to a breakdown of the valve body. https://www.google.com/url?sa=i&rct=...76328751709608


Hope that helps you out and I'm assuming you know you have to remove the transmission pan to get to the valve body. You can use the magnifier on your computer to enlarge it for easier viewing. Don't forget it could wind up being the converter it's not uncommon but I'm not sure it would throw that code that's why I'm leaning towards the valve body.LOL Good luck

 

This things 4l60e trans was fully built by a trans shop that does supposed good work from many sources in the area. It blew up on me six years ago on the way home and has been sitting ever since. Was at maybe 30% throttle when it let go. Zero reverse, no forward gears other than overdrive and that's sketchy. Had to remove the rear drive shaft just to get it to roll in neutral with 4x4 mode off then engage 4x4 to move forward again. lol, it's time to get this turd back on the road, hopefully getting a 4l80 into her, lost the turbo and go back to a stock engine until I get one built after the drive line is solid.