I just got a 99 F250 PSD, it had not been in 4wd in a while, now the hubs won't unlock.

My 01 F250 seemed to have strictly manual hubs. Turn right to lock, left to unlock. They may have been aftermarket, but on by the PO. Do I need to put some new Warns on the 99? Or can I lube then up and get them functional.

Price range for new ones?

Thanks!
Ed

 

try this http://www.guzzle.rbmicro.com/allube.html

 

Are you sure the hubs are locked, and the needle bearing hasn't locked up instead?

(Inner spindle bearing is the needle bearing where the axle stubs rides, inside the unitized wheel bearing)

You can remove the hubs by removing the snap-ring and gently persuading the hub to come out, sometimes with a rubber hammer

Then, reach around back of the wheel, and try to turn the u-joint by hand. You need to have both hubs out before trying this.

Report back.

 

Good question Krew. I will check it out this weekend when I go to pick up the truck. I just bought it yesterday and you could tell when turning that the front wheels were binding a little on tight turns on pavement, t-case was in 2WD. The hubs are in the unlocked position, but they still feel locked? I will know more this weekend when I take it apart. Thanks!
Ed

 

Yup, definitely check out that needle bearing. The ESOF hubs can get locked when they should be unlocked.

Something I've done a few times is:

With the engine off, turn the **** to 4x4HI.

Start the engine. Drive back and forth (on dirt hopefully) 10-20 feet.

Turn **** to 4x2.

Go back and forth 10-20 feet again.

Check to see if the hubs unlocked.

For whatever reason, at least the early ones (99-2001 possibly) you can get into a situation where the hubs are locked when they shouldn't be.

Moving the ESOF **** while the engine is off can get you into that type of thing.

 

you have probably read the link that was posted, and it is a good one, but you should know a few other options. The factory ESOF system is problematic, and can be a pain as time goes on. Your other SD has manual hubs that were installed, and this is a good fix that usually fixes about 80% of the problem. It is possible that the system has a vacuum problem, and will not disengage. The vacuum problem would suggest that the hubs would not lock either, but anything is possible.
These trucks also have a very poor unit bearing design that is not serviceable, and can also be a pain. I have seen some units made in China that are reasonably priced, but I question the units quality.
The replacement option would be to replace the unit bearing with an eliminator kit from Dynatrac. This kit replaces the unit bearing with an adjustable serviceable bearing, and aftermarket locking hubs. You will have the option of Warn premiums or the newest ones by Dynatrac. The kit can also include stronger 35 spline outer shafts too.
This kit is not the cheapest fix in the world, but very reasonable when you consider all that it has, and all of the upgrades that you get, and all of the hassle that you will eliminate in the future.
You can fix what you have, and maybe it will last for a while, or you can really fix it, and never worry about its performance again. With manual hubs the 4wd syatem will work when you need it.

 

Interesting, so this 99 F250 has vacuum activated 4WD hubs like a chevy but you have to lock in the hub in order to activate the vacuum assist?

Thanks for the tips is going forward and back and switching in and out of of 4wd. I am looking for a cheap quick fix for now. Not too concerned with reliability right now, just want to be able to drive it.

That is the one think I really liked about my 01 F250 with manual hubs and the 4wd lever on the floor. That thing has flawless 4WD!! Anytime I need it, it went it and out seamlessly, even into 4WD Low (when in neutral). I just want this 99 to work that well....

 

If everything is working properly....

with hubs manually selected to 'unlock' position...when you select 4WD inside the cab, the hubs are vacuum activated from 2WD into 4WD.

if you are running in normal 2WD and manually select the hubs to the 'locked' position you will of course now have the hubs connected to the differential through the axle shafts. And, you'll have 4WD when you select it inside the cab.

Now the fun part...if your hubs are 'gummed up' or worn, etc...the vacuum activation may not work for any number of reasons...bad yellow oring in the hub, outer hub gears worn or damaged, etc.

If you're having difficulty manually selecting the hubs, it's time to remove the outer portion and check them out, etc - it's easy as noted above - remove the outer snap ring and remove - you may have to coax them out with a rubber hammer, but they will come straight out. A good cleaning and re-greasing will usually cure this problem if the parts are in good shape.

If the vacuum activation still doesn't work, you'll have to check the lines, and if good, you'll have to remove the hubs entirely and clean and service - get new sealing orings, etc.

I went with the DynaTrac hub conversions on my 99 F-350, and now have to hop out and dial in the Warn hubs...but I KNOW when I'm in 4WD, plus I've now got stronger outer axles, and serviceable tapered wheel bearings! The vacuum lines are gonzo! Bad part is you'll need to find about $1800 for the kit! Too bad Ford doesn't offer the DyanTrac hubs as an option...it's really the only way to go, in my opinion...

 

I take it that it's ESOF? (Hubs say AUTO and LOCK) Barring the other spindle problems above, you can manually unlock the hubs by turning them to LOCK and then back to AUTO.

 

By turning the selector to LOCK, you are manually forcing the clutch gear inside to engage between the axle shaft and the hub's internal splines.

If the clutch gear is gummed up, or water damaged, etc...you may be able to force it into the LOCK position - however it may not UNLOCK when you turn the lever back due to too much crud inside. There is not a lot of spring pressure to unlock the clutch gear. If you can't get your hubs UNLOCKED, it may be due to the crud inside.

Take off the snap ring and remove the outer portion of the hubs to clean, etc...they should work again, at least by manually turning the hub lever...even if the vacuum part doesn't work.

 

A quick way to tell if the hubs are lock is to reach under and try to spin the front drive shaft by hand. It should spin free easy if they both are unlocked. Do this when the truck is turned off, in park and the t-case is in 2 wheel drive.

 

Thanks for explaining the lock/auto function on the hubs. Good tip on rotating the front driveshaft to check if locked or unlocked as well, thanks. I think the crud tip is right on. Salty Maine winters are hell on drivetrains. I will start with popping the snap ring, inspecting and relubing. Will start a new post with what I find. Thanks!
Ed

 

The only problem with that is if ONE hub is locked, the other axle will spin, and the driveshaft WILL turn by hand.

 

Ed, My 99 F250, was having the same probs. I went with a set of Warn 11690 hubs, and for around $200, it was a great upgrade from stock. Make sure when you install, that you don't use too much grease inside the hubs. Warn recommends around 1/32th of grease. Too much will cause the hub to get gummy and can cause malfuntion. The inner bearing will give you much grief if it has failed and will bind and cause a rumbling when defective. My gallery has pics of this type of problem. While your there, make sure the axle seals are also replaced if bad.

 

[QUOTE=Mexray]
If you're having difficulty manually selecting the hubs, it's time to remove the outer portion and check them out, etc

This is the problem I see with most of the complains on ESOF, doing preventive maintenace AFTER you have A problem. I service my hubs and stub shaft every 30,000 miles, I have 75,000 troble free miles on my 2004 F250.