If the truck has ESOF (electronic shift on the fly) just let up on the throttle and turn the switch to 2WD, the hubs will unlock by themselves assuming the manual override knobs out at the wheels have not been set to "lock". If so, those will have to be turned to "unlock" as well.
If non ESOF, make sure the floor shifter is in the 2 wheel drive position, then get out and turn the hubs on the wheels to "unlock".
If the above does not work for either type of system , there is an issue with the manual hub locks at the wheels and you will need to get them looked at.
if the hubs are working properly all u do is shift transfer case back to 2WD if hubs are not releasing you will have to check the hubs best idea change the auto hubs for warn manual locking hubs
It is Shift on the Fly but it has manual hubs. So you can put in it 4x4 in the cab but would have to get out to engage the hubs. So what i do is when i think i am going to need the 4x4 i lock the hubs before hand. Having the hubs unlocked reduces ware on the front drive tran and betters the MPG
push the 4X4 button located on the center console If you have a manual transfer case, you have to lock the front hubs, Turn the dials on the front hubs from "FREE" to "LOCK". The manual transfer case is "shift-on-the-fly". This means you can shift between 2HI and 4HI and back while moving. You must be stopped to shift from 4HI to 4LO or from 4LO to 4 HI. With automatic hubs the above answer will work. To disengage the auto hubs take it out of 4 wheel drive and drive in reverse for around 10 feet.
Shift into two-wheel high then turn the wheel locks to the free position. If you have automatic locking hubs, come to a full stop and hold the clutch in, if a manual, then shift to two-wheel high. Put the transmission in gear and roll seven feet backwards.
Put it in neutral then shift the 4WD lever in the position you want ie 4wd high range or 4wd low range, then you may have to hop out and engage the hubs at the front wheels. (follow the markings on the front of the hubs) Only use 4wd on loose surface never on bitumen, so don't forget to disengage the hubs.
If they are vacuum operated then it could be the hubs.
On your dashboard there is a 4x4 button. push it. The hubs will engage and lock automatically. If you want low range you have to be in 4x4 first then you may push the low range button
The Ranger has remote free-wheeling hubs to disconnect the front wheels from the front axle when 4wd is disengaged, reducing rolling resistance and hence tyre wear and fuel consumption. When you engage 4wd initially (when stationary) the free wheeling hubs engage automatically. Once these are engaged it is possible to shift between 2H and 4H and back when moving (e.g. when going between solid road and snow, since without a centre differential you can't safely drive the Ranger on-road in 4x4). This is why the free-wheeling hubs do not disengage automatically. To disengage them you press the RFW switch. This is the only time this switch does anything. If you drive > 60mph the RFW light will flash to remind you to press the button to disengage the free wheeling hubs.
You must stop,shift into neutral, then shift into 4x4 high/low and back into drive. To disengage, stop again, shift to neutral, then shift back in 2x4 and drive, for safety you should reverse about 10-15 feet to help disengage the shaft.
I have a 2005 which does have locking hubs, but that is so you can lock your differential from slipping. If you're stuck on a hill with all 4 wheels spinning, lock the hubs and your gear ratio is far apart, your front wheels won't spin, and the front wheels will actually do the pulling. Whether yours has locking hubs depends on the year of F250. Later F250's, I believe beginning with the 1998 models, do have auto-locking / manual hubs. The later F250 hubs can be activated manually or electronically. When you electronically turn on the 4wd ("shift-on-the-fly"), you engage the transfer case, front drive shaft, and front axle shafts. Also, when you electronically turn on the 4wd you activate a vacuum solenoid, which provides a vacuum source to each of your front hubs to engage them. The front hubs only connect the front wheels to the front axle shafts and has nothing to do with the front axle differential, which is an open differential unless you have a differential other than the factory installed piece.
Place the truck into nutral, push the 2H shifter into the 4H position and then put the car into reverse and back up about 12-15 feet. After doing so the clutche in each of the front hubs will be locked in. If you have manual locking hubs you will nedd to get out of the vehicle and lock them in manualy, and then repeat the procedure above. To disengage the hubs repeat the same procedure only in reverse (Pull the lever back into 2H).
The clutch will not engage ,you will not be able to shift./// the clutch will not (disengage ) making it almost impossible to shift gears