So im having some issues in my 5.3/4l60e swap in my 71 c10. So after going through it,the 3/4 clutch packs where completely toast. So during the rebuild, I went ahead and replaced the pistons upgraded the sunshell gear and installed a trango shift kit. So now that i got it back in the truck,im only able to move if i put the gear selector in 1st 2nd or reverse. If i put it in 3rd or overdrive it's like its in neutral,but if I disconnect the 20 pin round connector I have 3rd gear again but no overdrive. I hooked my scanner up and im getting a p0748 for the pressure contol solenoid, would this be the cause for it not wanting to go into 3rd unless its unplugged? Or could it possibly still be the low or forward sprag? Thanks for any and all help guys.

 

you rebuilt it yourself?
input sprag assembled backwards