I have a 2009 F-350 Super Duty 4X4 (automatic transmission, and with duallies).

The Operator's Manual has various instructions based on the the type of system included with the truck. Mine is manual (not electric), has a floor shifter for the 4 wheel drive, and has manual hubs.

My question deals with the hubs. The manual mentions 'Auto', 'Lock', and 'Free', as options on the hub.

My hubs only have 'Lock' and 'Free'.

So will anything bad happen if I leave the hubs on 'Lock' when I'm driving normally in 2WD? Would that be more or less the same as 'Auto' (which doesn't seem to be an option for me)?

Does 4 wheel drive engage when the hubs are on 'Free' but I have 4WD engaged on the shifter?

Obviously I'm a bit clueless about what goes on here. But the manual seems a bit nebulous as it covers all the options (and poorly at that) rather than just to my specific model.

It seems rather goofy that Ford would expect me to get out in the mud and lock in the hubs after I get stuck (yes I know I should do it before I get stuck, but we are living in the real world here).

 

I'd like to know the answer to this also. All I've heard so far is that you need to lock them in every now and then to keep things lubed up in there??

 

You only have 4wd engaged with the shifter on 4wd AND the hubs on lock. You can leave the hubs on lock without hurting anything but you might notice slightly lower mpg and it will bind making sharp turns.

 

With all due respect, I do not believe that locking the front hubs will lead to binding in turns. The front differential should prevent that in 2 wheel drive. If you experience binding, you may have a problem with the diff.
Best Regards,
Dan

 

When the hubs are unlocked, if you engage the 4wd, the front axle will turn, but no power will go to the wheels since the wheel hubs are not locked.

You can leave the hubs locked; it will not cause binding when in 2wd.

I manually lock my hubs at the beginning of winter, and leave them locked all winter long (and engage the 4wd when I need it).

 

I may be wrong, but doesn't putting the hubs in the lock position engage the hub with the axle? I could swear that running with the hubs locked in 2WD will turn the axle, and with the hubs in Free the axle is disengaged.

Then of course vice versa, with them in Free and in 4WD the trans turns the axle but the axle is not engaged with the hub. This sounds alot like the WARN hubs i used to run on my 76 Cherokee, 84 Bronco, and my 79 F250. Both manual trans, both 4 WD.

It's been quite a few years since I owned these (1986, 2001, and 1989 respectively), and i recall, that running with the hubs locked and in 2WD would cause strange ring gear wear in the front axle, potentially leading to early failure.

Feel free to set me right, but this is my understanding, and I tend to believe it logically, and think it is important.

 

I think it's important, too. That's really what I want to know, is it necessary to prevent damage by having the hubs 'Free'?

Having said that, I really can't understand why it would be engineered that way. Seems pretty crappy.

 

When the hubs are in Lock, but the transfer case is in 2WD, it will cause the front axle to spin because the hubs are locked to the axle, but no engine power is applied, because it is disconnected within the transfer case. It also causes the front driveshaft to spin, putting wear on all of the front axle parts as well as the u-joints in the front driveshaft. The system is designed to allow you to eliminate that wear by using the Free position on the hubs, which disconnects the front axle from the hubs as PJJTLC mentioned. Often people will run the hubs locked all the time, but do not perform the necessary maintenance on the front axle and front driveshaft u-joints, which can lead to catastrophic failures like the one shown in this thread.

https://www.ford-trucks.com/forums/1...1999-f250.html

I personally only lock the hubs when I am going somewhere that I think I might actually need 4WD. Many guys leave the hubs locked all winter, then unlock them come springtime and have no issues because the additional wear is only occurring for 4-6 months per year. If you are going to leave the hubs locked for any substantial amount of the year, my suggestion would be to be extra vigilant about performing the maintenance on the front driveline (checking front differential fluid level, inspecting front driveshaft u-joints, etc.) to prevent a catastrophic failure. Your mileage may vary.

 

Only lock em when when you need em. That's why they made that "free" position. Lock in your hubs and do a 70mph run down the highway. You will soon see why unlocking them is important.

 

I keep mine locked in almost all the time, only unlock them when I am going to do some extended highway driving. I routinely drive the interstate with the hubs locked, never any damage. I will confess that I do all recommended maintenance religiously.

I also need to use 4wd everyday to get to off road construction sites.

 

Here is a pretty decent article, which says it's ok to run locked in 2WD, but I'm sorry, if it's moving, it's wearing, if it's wearing it's heating, if it's heating it's heading towards the end.

http://www.4x4abc.com/4WD101/hubs.html
With that, do what you feel is best, but I lean towards the thought of, I don't need another surprise expense.

 

If you seldom use them because you live in a mild climate, I'd exercise them often, if it were me. It keeps them lubed and ensures they work when you need them.

 

If 400K miles with the hubs locked 75% of the time and NO failures is heading toward early failure I'm in trouble. I have been a Master Certified auto, light and heavy duty tech for 45+ years and have never seen a failure in the 4X4 system that was properly maintained that was NOT caused by something else, like running with transfer case engaged, not just the hubs, on dry pavement, spinning front wheels and hitting dry pavement or other high traction surface without backing off on power, etc. While you will see some odd wear patterns on the front ring and pinion from dragging it along, rather than powering it, they will be very minor and not detrimental. Just properly inspect and maintain the system and you will have no problems.

 

Maybe binding was the wrong word to use. While true the diff will make up for the difference in wheel speed between the two sides i can definitely tell a difference in feel if i leave the fronts locked.

 

I pretty much leave my front hubs locked all winter. It does not harm anything.

I have shifted into 4H at speeds exceeding 60 MPH without any adverse reaction from the truck.

Yes, you will feel some slight binding if you are making a full lock turn, otherwise you'll only notice a slight increase in drive train noise.