So, I have a 2000 F-250 H.D. V-10, Automatic transmission, and 4 wheel drive. I have the Electronic Shift On the Fly system, with the rotary ****. While hunting, I tried to put it into 4 wheel drive, by rotating the **** to the 4HI, position. Nothing happened. My hubs were in Auto, so got out, rotated them to Lock, and I had 4 wheel drive. Had to later shift to 4LO, and noticed on a sharp turn, the front end kept jumping around, like it was shifting in and out of 4 wheel.
Do I not understand this system? I read the manual, and from my understanding, if I leave my hubs in Auto, I can just turn the **** to get 4 wheel drive.
Anyone help me here?
Thanks

 

You either have a vacuum line leak to the hub or the inner seal is bad. Also the switch to operate the ESOF system is on the passenger side inner fender behind the battery. It is small and you may have to see a diagram to find it. It will have a couple vacuum lines that run to the hubs. These can go bad as well. I think mine is bad, but I just lock the hubs.


Do a search on the forum about how to diagnose the faulty parts. There are plenty of posts concerning this issue.

 

Thanks Diamnd1, I will look into that.

 

The "jumping" when in 4WD in a sharp turn is normal - the front end u-joints are not "cv joints" (constant velocity) so when the wheels are turned, the velocity at which the wheels spin is not constant in relation to the axle.

There are a variety of issues that can happen with the auto-locking hubs. From a broken vacuum line, to a bad vacuum solenoid, to the hubs themselves not latching, to the actual inner seal on the knuckle. It's the reason many install Warn hubs and do away with the auto hubs altogether. I did

There are some very good threads about it in the Superduty forum, you might have to hunt around for them a bit.

 

Do the Warn hubs still use the rotary switch on the dash? Or do you just get out and lock them in and out?

 

Warn hubs do NOT work with ESOF. Only OEM. I do not believe any aftermarkets will work with ESOF vacuum. Only manual mode.

 

The ESOF rotary dash switch does two things, it tells the vacuum solenoid on the pass fender to send vacuum pulses to the ESOF hubs to get them to lock if in AUTO and it controls the shift motor on the 4X4 transfer case. So even with Warn (or other makers) manual hubs that you have to get out and lock the dash **** still function as your selector for 2WD, 4HIGH or 4LOW.

 

Thanks for all the help. I will try and fix my existing system, and, if no luck just keep locking them in, or put in a set of Warn hubs. Would like to fix the existing system if possible.