i HAVE A 2001 FORD F350 SUPER DUTY DUALLY DIESEL. i USE AUTO HUBS 10 TIMES A DAY TO GET UP MY DRIVE WAY ( GRAVELED HILL ) CAN'T MAKE IT WITHOUT THEM. i HAD THE AUTOS GO OUT AT 10,000 AND 50,000 AND NOW AT 75,000 MILES i HAD TO REPLACE THE DRIVERS SIDE HUB AT 10,000 BEARINGS WENT OUT. SO i GOT INTO THIS PROBLEM EXTENSIVLY. THERE IS A VACUM LINE TO EACH HUB, WHEN YOU FLIP THE SWITCH IT PUTS VACUM TO THE HUBS AND PULLS THE GEAR ON THE HUBS INTO THE SHAFT. ( AND ALSO ENGAGES THE TRANSFER CASE. THE VACUM SWITCH IS ON THE FIREWALL ON PASSENGER SIDE. THERE IS A RUBBER O RING ON THE WHEEL BEARING HUB AND ALSO ON THE AUTO HUB IF WORN OR BROKE YOU LOOSE VACUM IN THE WHEEL BEARING HUB WHICH WILL NOT LET IT ENGAGE. ( PRETTY HARD TO PULL WHEEL BEARING HUB AND REPLACE O RING ) BUT THIS IS THE PROBLEM THAT i HAVE HAD 3 TIMES. yOU CAN PUT VACUM ON THESE LINES WITH A HAND HELD VACUM PUMP TO TELL IF THE O RINGS OR HOSES ARE LEAKING. I now run with hubs locked in all the time and just flip the switch when i need 4 wheel drive . Have been doing this for 20,000 miles with no adverse effect except gas milage.If you need you can e mail me at brmorse1@comcast.net and I will try to explain better.
brmorse1

 

well my '04 f250 has 18k on it, i use my 4w atleast once a week if not more depending on weather and for pretty good distances and havnt had any problems yet, im sure ill let ya all know when i do, 1 thing one of the post farther back the guy said something about disengaging issues i just wanted to say that the owners manual talks about having to go in reverse once you have switched to 2w because of the torque on the hubs or case or whatever, just an idea

 

[QUOTE=brmorse1] THERE IS A VACUM LINE TO EACH HUB, WHEN YOU FLIP THE SWITCH IT PUTS VACUM TO THE HUBS AND PULLS THE GEAR ON THE HUBS INTO THE SHAFT.


Well it turns out it was the vacuum lines. I fixed the problem for about $6.00. Thanks!

 

I don't have a problem with the auto hubs locking, it's just that they won't unlock right. I took the hubs off and taking them apart at least to the diaphram they are ok, but from the diaphram out to the **** it seems that when you lock manually it is ok but when unlocking, the diaphram and the piece between the **** doesn't want to go back in except when forcing by hand. Question I have, does anybody know how to get the **** or the diaphram out so as to clean out the manual part of the hub without breaking anything. I'm thinking that there is dirt or crud inside that part that won't let it work right. My fingers hurt!! Thanks Rob PS this is on a 2001 F-250

 

I need help in trouble shooting my 2000 F350 psd 4wd ESOF and advice. The selector is engaging the transfer case when the **** is turned. The hubs can be turned to the lock position with my fingers or in the case of the passengers side I have to use pliers and 4wd will work, if left in the auto position they will not work. After reading several posts here I have narrowed the problem down some what. I would like any help narrowing it down further. With the hubs in auto if I start down the road and select 4hi and the heater is on vent it will go to the defrost-I know vacum leak. But is there a way of narrowing this leak down. The second problem is how hard the passengers side is to turn to the lock position. This problem first started (I know now) as a problem with the hubs unlocking approximately 16 months ago. I replaced one hub with ford unit from dealer in August 2004 $83.00, the same hub today is $243. our cost $183.00.

 

Take the lines off the hubs and cap them and see if you still have the defrost issue, leak.
Stock hubs are junk I don't know what to tell you. Get warn manual hubs. $170 a pair and you'll have to get out.

 

99f350 Is snowing heavy here tonight and I am now at work been a police sgt for 26 years. Locked the truck in manually. I agree with your warn comment I just thought I could return to esof and a factory hub cheaper. This is not the case. Through one of the sponsors on this sight I have found warns for pretty much the price you said 172.. and I understand there is no comparing warns to the factory plastic pot metal things that have little ball point springs in them. If the one hub would turn a little easier I would just engage them manually which incidentally would be the same way warns work. thanks for your input.

 

I capped mine off right before the vacume selonoid behind the battery. I siloconed up at bolt around the same size as the red vacume line at the selonoid and stuffed it in the line connector. No more vacume leak but no more acutall ESOF, I don't mind locking in my hubs though. Mine are still turnable by hand at 110K but I try to lock them in quite a bit. I think most people have been plugging there line in this spot. Sorry if I repeated someone. Good luck

 

Will the esof vacum lines simply unplug at the axle housings from the metal inserts/nipple. And do they just unplug/snap where they attach to a different hose in the area of the wheel well. If I just touch my vacum lines I get very black hands. I do not want to seem hard headed but my truck has 122,000 miles on it. I plan to replace the ball joints (however I get no movement in the wheel/rim when it is jacked up) but I do get a noise when braking from the drivers side it is kind up a dull thump and is either the brake hanging up or calipher or the ball joint I can not tell the pads were recently replaced and I did not notice noise before. But while replacing ball joints I was going to replace the hub seals, inner and outer axle seals and clean and replace the vacum lines nipples. If vacum leaks are still present then I was going to cap it at the solenoid and if unable to free up hub on left put the warn premiums on.

 

Yes, mine had some goofy zip ties on them from the factory. When the hubs worked I put some small hose clamps on cause the zip ties weren't quite doing it. Yes I believe I also was able to unplug them at the little plastic coupler by the wheel well(could be brittle). My ball joints were replaced at 95K and I did have the little clunk in the front drivers also, jacked up I only had play when I lifted up on the driver side wheel, and they were very stiff too. Most vacume leaks are not the lines, it's usually the hubs. My hubs work yet but will be replaces with WARN's when the time comes. I'm not sure but I don't think you can just replace the hub seals you may have to replace the whole hub assembly. Good luck

 

the hub seal I am referring to is not on the lock in lock out but on the actual wheel hub to knuckle at ford this part is approximately $3.00 the large axle seals are aproximately $30.00 a piece and the smaller ones are $14.00. I do appreciate any info that you or anyone else has. Would you or anyone else know if I unhook the vacum lines at the nipple on the axle housing and hooked it up to a vacum gauge what type of vacum should the gauge show.

 

How do they get the vacuum to the hub?

 

Diesels do not produce vacum in the way gassers do so there is a vacum pump or at least a solenoid looking thing with two vacum lines on it-1 is red and the other ones is black. This is in the area of the passengers side engine-kinda of behind the battery. Two hoses run down through each fender well and eventually attach to a metal nipple in the area of the axle housing knuckle(this is on the 99,00,01 and maybe other years that have ESOF only the ESOF electric shift on the fly. Also the hubs will have two positions on them if the writing has not worn off -they will say "auto" and "lock". This system is unusual or at least awkard if you have used the other Ford systems in years prior to 1999. Just look at all the posts involving hubs and esof in super dutys. All that being said mine worked fairly flawlessly for 90,000 miles.

 

Sorry, don't really know how the diesels work too well, I have a v10. But I know that(at least on the v10) that the hub's don't get straight vacume to lock, they are supposed to get a pulse from the selonoid to lock them and another pulse to unlock them. I read a post a while back and someone mentioned the amount, it's like 14 units(don't know the units) to lock them in and like 10 units to unlock them. Don't quote me it's been a while, but I know I could not pull any vacume with my pump when I tried on each hub so I just plugged the line at the selonoid and then my defrost didn't turn on when I locked it in 4wd. Sorry I couldn't be more positive about about the actuall vacume.

 

thanks anyway the only reason I'm so persisent in attempting to fix the esof is my brother in law bought a new ford hub to replace one of his. He then got disgusted with the esof and ford hubs and as he works part time at Oreillys he got Warns for cost and put them on. He has offered to sell or give me the ford hub even getting the ford hub free now there are $183 to $238 I am still debating whether to just buy at ($172) and put the WArns on. Not much of an advertisement for the Ford hubs is it.