I have an 09 f150, 5.4 that I can't get to engage in 4x4. I have read a bunch of threads and other stuff online and can't figure it. I apologize if this is answered before(I'm assuming it has been alot).
here's the issue. I tried to engage my 4x4 awhile ago and it wouldn't engage and I got stuck trying to go up a hill in 2wheel drive. ( I tried to engage it on flat ground with my foot on break). Later i changed the vacuum solenoid, still no 4x4. I pulled the lines off and have vacuum like it should. I can hear the transfer case motor click. I even put it in 4low and the truck moves like its in low gear so I'm assuming the TC is working. I pull the lines off at the iwe and had slight vacuum. My questions are if I select 4hi and pull the lines from the iwe, I should have 4x4, correct or am I misunderstanding how it works? My other question is could both iwe be bad and not engage(I thought they fail safe to "locked" if they malfunction)? Any help is appreciated

 

Yes, when in 4x4 the vacuum should go off, and that is the 'default' position for the IWEs.

But, yes, they can also be broken in or out of 4x4. Or it could be something else. Have you read this one: https://www.f150forum.com/f72/how-di...m-esof-186872/

In other news....What are your tires like?

 

That's a good thread to look at, if somewhat lengthy ^^^^^^



Jack up the front wheels, with the engine off, rotating the front wheels by hand should result in the CV axles turning with the wheel, with the engine on, and in 2H, they should not turn when you rotate the wheels.

 

yes, I've read that link, very helpful. It made ir so i actually understand how this type of 4x4 works(i think i understand lol). My tires are great, only been on since mid summer. No uneven wear or anything out of the ordinary. Thanks for the quick response

 

Thanks for the help. It turns out the my iwes were either gummed up and wouldn't move out on their own or the springs were bad and didn't push the iwe out. I'm gonna be replacing those as soon as they arrive. In the mean time I got the iwes to engage by unhooking the vacuum line at the iwe and using compressed air to push them out to get them to engage. Needed 4x4 now and couldn't wait. Lol