I have a 98 Dodge 2500 4x4 diesel. No problems with converter lock up until after rebuild. When converter locks up, engine will flare 300 to 800 rpm with light throttle pressure. I have been building transmissions for 20 years never to run into this problem. This is the 3rd one in two years with the same problem. I have installed billet converters, Transgo shift kits. It seems like the converter is not getting enough lockup pressure. Line pressures are right on the money. We have changed gov. solenoids and sensors, TCC and 3/4 solenoids to no avail. Any help would be greatly appreciated!!!!

 

It looks like you are looking in the wrong places solenoids and sensors ONLY give input. first thing I would do is back track WHAT YOU changed. what did you do in the valve body? pump? input drum? cooler circuit? all of these are in play with the converter. also sent a PM