'05 SCrew Lariat, 130k

i've kinda been ignoring it for a while now cuz its been intermittent. I suspect that this has somethin to do with the vacuum solenoid for the system, any quick/easy way to confirm this? what is the part number I need to get to replace it? and are there any links to some "how to's"?

I've used the search function but apparently I'm not real good at using it cuz I haven't found much about it.

Thx!!

 

Yea, unplug the vaccumm lines at the solenoid this should lock the axles and hubs together if it doesnt then the actuators are seized inside. Lift the truck off the ground and see if they are locked together (car doesnt even need to be on).

 

Search IWE . you will get all the answer . good luck

 

We need some more information on "not engaging." Does the 4x4 light on your dash come on? Do you have the Electronic Shift on the Fly (ESOF) or the manual transfer case lever?

 

no dash light, ESOF

anything else? I've been seeing this intermittently for some time (couple years but it always 'came back', now it is not.

 

I have a feeling its the common issue of the vacuum lines being clogged with rust (blow up with air hose), solenoid, and actuators (the solenoid is the one that can cause the light not to pop on).... Or worse its your transfer case but I doubt it (does the 4x4 LO come on?)

 

4x4 LO light does not work either

 

Given the symptoms you noted, I'd say your ESOF motor is going bad. Check this thread out:

https://www.f150online.com/forums/20...ore-snows.html

 

had a similar deal, it would click and the 4X4 light on the dash would only flash. Once in 10 times it would work.

I pulled the plug apart (on the passenger side firewall by the cowl) cleaned the connections up a little bit and put it back together with dielectic grease. fixed it for me.