Sounds like part of your problem may be reversed vacuum lines on the transfer case; not sure about the 4-low unless the computer disengages the transfer case if it senses the hub lock is off.Hi Clint, how did you determine your 4wd computer was shot? my LJ is doing some weird s***, i have manual hubs but it is only going into 4wd when the hud switch is on and the 4wd is off, and i have no 4wd low at all, as soon as i put it in low the light flashes then goes off.
if you have any insight please pass it on.
thanks