4x4 won't engage

[burk0711]

Hello,
I have a 99' F250 7.3 Diesel. I have been having problems with the 4wheel drive popping out and now it just won't work. I replaced the pulse vacuum hub lock solenoid and now the new one is bad too. I want to know if I can switch the hubs to the old school hubs that are locked or free? Or if anyone else has had this problem and what they did to correct it. I have replaced the engage motor also.
Thanks in advance

[old school]

the auto hubs dont work that well u can change the hubs out no problems just as long as its not a dually model hubs cant handle wieght what u can do to check your hubs is look over top of tire check and see if u can free spin axle shaft if u can the turn hub to lock postion if the axle stops turning and u can turn back to auto then hub is good check both sides the transfer case acutuater had problems in that year 1999-2001 hi can be
shifted in drive but low only in nuetral at a stop then drive,have someone in cab key on not ruuning u under truck with it in park rotate drivline while person in cab turns switch if drive line stops acutuater is good possible your hubs are unlocking them selfs if 1 hub unlocks 4wd doesnt work because its a limited slip,hops this helps

[trucksnmud07]

One of my buddies is having the same problem and cannot figure what is wrong. Could it most likely be the transfer case actuator? What else could cause the 4x4 not to engage?

[old school]

try the things i listed in previous post its the easyest way to test k

[graham567]

I had a similar problem my 4x4 just would not work period. But I just replaced the fuse and everything worked again.