Hi all, I have a 91 pickup 4 cylinder 4x4, started to have issues in reverse (did not want to go in, and would hit the transfer case shifter each time) it would also need a lot of gas to keep the truck from stalling happened in first too. I've replaced the master and slave cylinder and ran a new line to them too, now when i start the truck, it won't go into gear HOWEVER if 4WD is on, it will shift into gear, but will not move. any help is greatly appreciated, noob mechanic and i've been working on this problem for almost a week straight with one road block after the other.

 

Update, the gears will not engage in 4wd now, not sure why they were before, will shift fine if the truck is off. system has been bled, the slave is moving and pressing i believe the clutch fork?