Chevy 2500 Issue

[redchevy25]

my truck is a 95 chevy 2500 with a 4l80e tranny 4wd. with the 350tbi. right now it is stuck in limp mode but inconsistently shifts perfectly and then it wont shift after i turn the truck off and come back to go somewhere. ive been battling this for over a month and a half and have replaced the tcm changed the drac or vss buffer chip and replaced the vss input because my tach and speedo seem to not work sometimes with this problem. the last time i had it scanned it came up as a shift solenoid b problem. Could i need a new vss output or is it a wire problem is my question