My Super Duty has a problem with the left front hub sticking. I use the truck for logging and have recently driven through some deep mud. The hubs are in the auto position. The right one seems to work fine, but the left one is frozen in the auto position. When the left front wheel rotates the left hub makes a grinding noise. Although when I engage the four wheel drive the grinding stops and then it reappears when the switch is turned back to two wheel drive. Am I able to remove the front hub and clean it out or are they sealed and have to replace it with a new one? It definitely sounds as though some mud or dirt has made its way in the hub.

 

the hub is sealed and thats a pretty easy fix as long as it comes apart from everything. not too expensive either i dont believe

 

HEY LOOPY,
THIS MAY HELP TRY THESE THINGS AND ILL CHECK BACK LATER THIS EVENING AND CHECK UP ON YOU.
Hublock Operation
The Super Duty and Excursion 4X4 ESOF system uses timed vacuum sequences to lock and unlock the wheel ends. A high vacuum level is used to engage the hublocks, and a lower vacuum level is used to disengage the hublocks, after which the vacuum is released and the hub lock holds itself in the proper mode. The vacuum signals are supplied to the hublocks by system components, including the GEM, wring harness, solenoid, vacuum harness and vacuum seals. As the first step in service, eliminate such obvious items as loose wiring connectings, loose vacuum connections, or damaged vacuum lines.
Disengage Time
"Slow" release of the hublocks is not considered abnormal for this system. Anytime vacuum is applied to the hubs, whether for 4X4 or 4X2, the hublocks will initially engage. If 4X4 was requested, the hublocks will remain engaged, but if 4X2 was selected, the internal mechanism will release only after the GEM timers expire and vacuum is vented from the hub. This normally takes 15 seconds, but can take up to two minutes, depending on how the 4X4 mode select switch was operated. After the hub mechanism releases, internal springs must work the hublock gears to the disengaged position. Road bumps, vehicle speed, acceleration cycles, or momentary reversal of direction can assist this process, varying the length of time the hublocks remain engaged in each situation.
Manual Override
The hublocks have manual override selector dials, which, when rotated to the "LOCK" position, will keep the mechanism locked regardless of the instrument panel 4X4 mode select switch position. Verify that both dials are in "AUTO" before evaluating ESOF operation.
Hublock Replacement
Left and right side hublocks are not connected, other than by the common vacuum supply line. If a malfunction in either hublock is diagnosed, it should be installed as an individual unit; there is no need to "balance" an axle with new hublocks on both sides. If both sides appear to be malfunctioning, be sure to verify upstream integrity before installing new hublocks on both sides.
Many system components are involved in the proper operation of the ESOF hubs on 1999 and newer Super Duty and Excursion 4X4 vehicles. Before diagnosing the hublocks themselves as the cause of 4X4 concerns, be sure to verify all related system components.
After removing the hublock retaining ring be sure not to use tools other than the hands or "grip" gloves to remove the hublock, as damage may occur to either the paint or the function of the hublock. Pliers or locking Channel-Locks® should be considered as a last resort, and will usually damage the hublock, making it necessary to install a new hublock
CHECK THE VACUUM AT THE KNUCKLE:<O</O
1) MAKE SURE HUBS ARE IN THE AUTO POSITION
2) JACK UP UNIT SO THAT THE WHEELS ROTATE FREELY.
3) DISCONNECT VACUUM LINE AT THE KNUCKLE THEN ATTACH A VACUUM GAUGE ON THE LINE
4) CHECK FOR VACUUM WITH ENGINE AT IDLE SWITCH MOVED FROM 2WD TO 4WD. <ST1NORMAL</ST1 OPERATION APPLIES ENGAGEMENT VACUUM FOR 45 SECONDS AND THEN DROPS TO 0.
5) IF THE VACUUM IS GREATER THAN 10 IN-HG THAN THE ENGAGEMENT IS FUNCTIONING PROPERLY.
6) TURN THE SWITCH FROM 4WD TO 2WD. <ST1NORMAL</ST1 OPERATION APPLIES DISENGAGEMENT VACUUM FOR 15 SECONDS THEN DROPS TO 0.<O</O
7) IF THE VACUUM IS BETWEEN 5.8 & 7.3 IN-HG THEN THE DISENGAGEMENT VACUUM IS FUNCTIONING PROPERLY.
NOTE IF EITHER TEST FAILS THAN THERE IS SOMETHING WRONG WITH THE VACUUM SYSTEM, LEAK, VACUUM PUMP, SIGNAL TO VACUUM PUMP ECT.<O</O
<O</O
CHECK FOR MANUAL ENGAGEMENT OF HUBS<O</O
IF THE UNIT ENGAGES AND DISENGAGES MANUALLY, THEN CHECK THE HUB FUNCTION OFF THE TRUCK.
1) REMOVE THE WHEEL
2) REMOVE THE RETAINING RING, PULL OUTWARD TO REMOVE THE HUB LOCK.
UNLESS YOU KNOW OF SOMEONE WITH THE SPECIAL TOOL WHICH TESTS THE HUB VACUUM FUNCTION IN THE HUB ITSELF. YOU WILL NEED TO GO TO THE FORD DEALER AND GET THEM TO CHECK THE HUB FUNCTION FOR YOU.
<O</O
THESE STEPS SHOULD GET YOU IN THE RIGHT DIRECTION.<O</O
HOPE IT HELPS LET US KNOW WHAT YOU FIND OUT. <O</O
<O</O

 

This may help as well:

Welcome to guzzle's 4x4 Autolock Hub Lubrication Maintenance Web Page

You should manually turn those hubs by hand at least once a month to ensure they are properly working.

 

In addition to Senix's link, you should consider lubing and protecting with Fluid Film. In my experience, I feel Fluid Film is the BEST lube/protection for auto hubs by far!

 

The left hub is stuck in the auto position and will not move to lock. The right one moves freely.

 

So you need to take it apart and lube it..

 

Thanks for the info guys. I'm on it.

 

Cleaned and repacked the hubs. Problem solved!!!

 

so just rotate monthly and run them a couple miles and they will stay in much better shape.

 

Cool glad it is fixed.