99 ford f250 super duty four wheel drive. Has new hubs and new warn lockouts. Has electronic switch on the dash. 4x4 light comes on but four wheel drive will not engage. also no high or low lights come on dash. Just 4x4.lights up?? What do you think?? Thanks Bob!!

replacing bearing involves removing axle your not replacing a hub but tearing apart axle 99 04 F250 Sterling Rear axle bearing replacement Pt 2 2006 Ford F250 rear hub axle seal replacement F250 Rear Brakes Axle Hub Removal Install 03 07 Powerstroke

Do you have mechanical-shift four wheel drive,or electronic-shift, 4WD system ? Any lights lit on the dash ?
The electronic-shift, 4WD system consists of the following components:

• Transfer case (For transfer case repair procedures, refer to Section 308-07B ).
• 4WD control module (For 4WD control module installation, refer to 4WD control module in this section.)
• Mode select switch (MSS)
• Gearmotor encoder assembly
• Automatic locking hubs (hub locks)
• Pulse vacuum hub lock (PVH) solenoid and vacuum lines
• The mechanical-shift four wheel drive (4WD) system consists of the following components:
• Transfer case (For transfer case repair procedures, refer to Section 308-07B ).
• Transfer case shift lever
• Manual locking hubs
• 4x4 indicators
• Shift linkage (hub locks)

replace locking hubs

The little motor on the transfer case is prob out. Check it

im not sure if a 2000 f150 and a 2000 f250 have the exact steering column,but incase it is then check at the base of the column inside and you may see a triangler shape bracket that the shift cable connects to,there will be 2 torque screws holding the bracket to the column,either a t-20 or t-25 not sure,they may be loose so the shifter will be sloppy...my 2000 f150 had that problem and i stumbled upon it,it seems to be a 2000 year issue...about the manual hubs,try locking them in and drive forward and reverse very slow a few times,if they lock in then they are sticky and it takes time for the spring inside to push then together.lock the hubs in first,then after a while shift to 4x4,because if they are just sticky,it may strip the teeth on the lockouts from the axel turning against the inside of the lockout.

transfer case selector switch or equivlent to is bad or connectors to the switch is bad dose it do only when it rain or moisture underneath.

The front hubs are vac. actuated and the lines are know to get a leak in them. When it happens the front hubs won't lock.

I have the same hubs on my truck as what you have. I have been told it can be done you just have to know if you have a dana 50 or 60 front axle. The warn hubs i'm sure are a better quality hub but if your worried about the auto feature of your current hubs. That is vacuum accuated when you 4 wheel drive is engaged. And there fore vacuum engaged. Mine used to work great but after a lot of mudding sand got into seals and vacuum didn't work anymore so i treat them as free/lock hubs.

I suggest you check for vacuum leaks in the 4x4 actuator switch, and/or at the hubs themselves. My 99 has had issues like this and I recently changed out a leaking switch and plan to service the hubs soon and replace the o-rings in the hubs and lube them. Also listen for the vacuum pump to come on when you turn the key to on. These vacuum hubs do not impress me at all and are a constant source of internet talk. Good luck. I am not a mechanic and just offering my experience as an owner.

i have 2006 f250 4x4 will not engage unless i lock in hubs. once hubs locked in i can engage 4x4 by using electronic selector. why will it not engage when hubs are in auto and electronic selector is on 4high