I'm probably having a moment but...

My 2000 F250's axles didn't turn until I engaged the dash switch, normal right?

Last night I was following my wife and noticed the front axles spinning on our 2000 Excursion. I double checked to see that the hubs were set to 'manual' and they were. So what's the deal? Are my hubs messed up?
I thought if there was a problem with the vacuum system the front end would NOT engage. I'm leaving on a 4,000 mile road trip Friday and I want these axles to stop. It's gotta be digging into my mileage plus I don't want the extra wear. Thanks guys.

 

What do you mean by axles? The knuckle sections holding the wheel onto each side of the axle?

I am going to go out on a limb here and take a stab.

The axles (or shafts) are going to turn because the vehicle is moving, you don't have a choice in that matter since they are attached to the wheels.

I could be wrong, but if your hubs are set to manual then they are engaged. Where as if they were set to auto, they would be engaged via vacuum when you switched the vehicle into 4x4. If the vacuum system wasn't working, then you would manually switch the hubs over to engage them.

If the hubs are disengaged then this would mean that your front driveshaft should not be spinning. If they are engaged, then your front driveshaft should spin when the vehicle rolls in either direction.

Easiest thing to do is get under there with the vehicle set in 2wd. Your front driveshaft should spin freely by hand. If it doesn't then you hubs are engaged or you have a problem with your transfer case.

With the vehicle in 4x4 and the hub engaged or dissengaged, the front shaft shouldn't spin freely at all.


Judging from the mods to your other vehicle, I am sure your just having a momment. However, I could be completely wrong in my explenation. I haven't driven my truck since the engine blew up two months ago.

 

Yes sorry, axle shafts. I didn't check the front DS but I'm sure the front wheels should freespin when on the hubs are set on auto. I may be wrong but I think when the 4wd switch is selected and vacuum is pulled from the hubs, they engage thus locking the axles with the wheels and front driveshaft. At least I thought that was the point of the system.

 

Looking back on what I said, you wouldn't need hubs if the wheels didn't free spin.

I am working a night shift so I could just as easily be confused. If they were set to manual when you watched your wife drive, wouldn't that have been normal for them to spin?

 

Yeah they should free spin, my F250 did.

 

On the ESOF, there is no manual on the hub. You have AUTO and LOCK. Make sure the hubs are set to AUTO.

 

Lock is what I was thinking when I said manual. Sweet god I need some sleep.

 

Are you saying I don't have vacuum lines actuating my hubs, does only ESOF do this? I have both vacuum lines and auto/manual hubs.

I checked that they were on AUTO first and even cycled them from lock back to AUTO. Cycled the dash switch too. One thing I need to try is maybe back up a bit to see if it unlocks the T-Case. I know other trucks sometimes need this to disengage the Tcase, maybe this is the same.

 

I know that's what you meant, I keep saying it too. It really does mean manual lock .

 

Why can't I edit my first post? I can edit the last two. Anyway, I meant to say,

I made sure they were set on AUTO and they were NOT manual or lock.

 

LOL, OK. Yes, try backing up and switching while moving. With your hubs in the auto position and the switch on 2wd, you should be able to turn the front drive shaft by hand. If you cant turn the DS by hand, you will need to look for a vacuum leak. You may have a hub not unlocking, or your transfer case is not disengaging.

 

With the ignition switch on (truck not running) you can hear the hubs engage or dis-engage when switching your ESOF, or at least I think that’s what’s going on. Either that or its the solenoid that I'm hearing ‘cause I don’t think there is an accumulator that stores air. Anyway, try that, it’s a starting point on if its trying to engage.

 

All fixed... for now. I replaced both vacuum lines at the wheels, old ones were totally grody and rotted. I then started the truck, backed it up, cycled the switch, went to 2wd, pulled forward, hopped out and the shafts would spin freely by hand. Not sure exactly what the cause was, maybe a vacuum leak? If so I thought the hubs would default to auto or open, maybe not.

Anyway, thank you all for your help and I'll keep my eye on them or hands rather .

 

Any other symptoms? A bad u joint will cause the shaft to turn (and wobble). After a while, there will be a lot of vibration though.

 

Not that I saw, these were obviously engaged via the hubs. While changing the hoses, I tried to spin the u-joints and they stopped left to right with a slight bit of play in between. They're free spinning now.