hey guys I've got a question for you all again, my 2000 f250 s/d powerstroke while driving down the road the 4x4 light flashes on and off, and it truely sounds as if the front end is trying to lock up even while the selector switch in cab is in 2wd position, i do have the autohubs and they are set in auto position, I'm not sure what makes the front hubs decide when to lockup, any ideas what might be going on?


Thanks in advance

Dave

 

I had this exact thing happen to my 04 about a month ago.

First go out and make sure your hubs aren't locked by turning the front drive shaft with your hand. If it doesn't spin one or both are locked. Try turning the 4x4 switch a few times until you can get it free.

Once you have confirmed the front drive shaft is free, unplug the 4x4 vacuum solenoid. It is right next to the vacuum pump on the passenger side quarter panel under the hood. Has sort of an offset vacuum hose adapter that plugs into the side of it.

Drive around for a bit and see if this solves your problem. If it does, your solenoid is bad and you will need to get a replacement. They just changed the part number again and the correct # is: 7C3Z9H465A. (Confirm this with whomever you order it from that it will fit your 2000. That's what I used for my 2004. SilverStateFordParts.com (formerly DirectFordParts.com, a sponsor here) sells them for $40.49 + shipping. Call them up at 702-796-2762 or log into their website and submit an inquiry. Ask for Alan or Brian and they will get you setup.

 

When you say "flash on and off" does it do a regular flashing, or does it randomly go on and off?

The vacuum system for the ESOF should never flash the 4x4 light.

The 4x4 light only lights when the GEM module thinks the transfer case is in 4x4.

What do you mean when you say "it sounds like it's trying to lockup" ??? Transfer case or front axles?

 

4x4 light flashes intermittently, i notice it more when pulling a trailer, but have had it happen when running bareback also (trailer weight doesnt seem to be a matter it does it empty and loaded) the front end seems to be locking up while driving down the road randomly, I picked it up on a hoist yesterday and the front driveshaft did turn freely, which doesnt surprise me seeing as the light wassnt flashing or on front wheels spin freely I did find a rear U-Joint that was just about gone so im gonna replace that this weekend and i pulled the front hubs off and cleaned em up inside and soaked em in marvel mystery oil (If you have one of them food saver vacuum sealer units take your hubs apart and soak em in one of them bags with some thin oil, sucks the oil into all the little nooks and crannies, loosens everything up really nice) dumb question does the front hubs lock up right away as you turn the switch or does it need to sense some slippage before it locks up, Okay one more question, does this gem module happen to do anything with the brake controller unit seeing as that seems to have quit working about the same time, i assumed it was a blown fuse or something so didnt worry it yet seeing as i didnt need it

 

The hubs should lock right away, or at least, with very little rotation of the axle versus the hub.

Again, the 4x4 light is triggered by the switch on the transfer case. It has nothing to do with the hubs.

 

Hey all,
So far info is very useful regarding the part numbers and such, BUT I am still confused regarding the split off the celenoid to the heater system. My mechanic pulled the vaccume tube of the selenoid, plugged it with a screw and told me I needed a new one. Now the heater/ Air conditioner control switch for the floor to defrost works fine. Mechanic says there is no FWD now. Does this vaccume assist in pulling the mechanism out of FWD or putting it in. If I turn dial to 4WD high, I hear it click but when i turn dial back to 2WD I do not hear it click back. The Excursion feels like the steering is a bit tighter, could that be from the 4WD not fully releasing back to 2WD?
2000 Excursion 4WD 7.3Dsl
Thanks

 

The problem is the vacuum is leaking through the solenoid. So when you try to switch the A/C controls, it's not pulling enough vacuum to change it. If you plug the line it will keep the vacuum, but if your truck is still in 4wd, it needs vacuum to unlock the hubs. The solenoid locks and unlocks the front hubs with vacuum pressure.