Last week I started to notice a slight buzzing/humming sound when the vehicle would move. I lifted both front wheels off the ground. Started the engine. I spin the passenger side wheel and the CV shaft spins with it. I spin the driver side wheel and the CV shaft does NOT spin with it. I put truck in 4wd. CV shafts now spin with both sides.
So my passenger side is staying engaged.

I've checked all the lines, they look ok and I have the updated solenoid. After reading another post on a similar issue, turns out he had a bad check valve closest to the solenoid. I blew through that check valve and air blows through both sides. The check valve closest to the intake manifold only accepts air one way. Is this likely my problem also?

Also, is it safe to drive it like this till I can fix it? I have not heard any grinding or any harsh noises like some do, just a slight hum. Barely noticeable.

'05 STX 4x4

 

sounds more like you new a new hub assy..

 

Having a check valve that is shot isnt helping anything, but is a place to start. Replace that check valve and see what happens, if your noise goes away then your probably fine, if not, then your passenger IWE needs replaced. Your best bet is to get a vacuum guage and go through this post and test your lines and parts.

https://www.ford-trucks.com/forums/8...ml#post7322441

As far as driving like that until you get it fixed, if its only going to be a day or two and you not going very far, you are probably ok but if you have a long distance to go or several days until you work on it, i find the check valve in the line coming right off the engine and disconnect the line from the check valve and plug the side going to the engine to prevent the engine from just sucking air. This method will lock your front end at the wheels, but you will not be in 4wd.

Everytime you here that hiss/grind, its the gear on the IWE trying to mesh and grinding with the gear on the CV shaft (not good) So, do some checking and see what you find.

 

Ok well I just did some more fumbling with it and now I'm getting the clicking when rotating the wheel. The CV shaft isn't moving but I hear clicking like cards against spokes of a wheel. And it's slow to respond to the change (vac or no vac).

Looks like it's a new IWE for me.

Thanks, btw.

 

This is completely up to you, and its hard to diagnose over the internet a car problem, but what i would do is get a vac guage and check the IWE and lines, $30-40 at the parts store. Then you can tell for sure if its a IWE or wheel bearing. Im not saying its not the IWE or not the wheel bearing. But i think it would be cheaper and less agrivating to spend a little money and do some tests and buy one part than to buy one parts to then find out its the other you need. Then you also have the tool for other uses as well. Just my 2 cents

 

Alright I borrowed my friend's vacuum pump and went at it. Pumped the passenger side up to 25 in Hg and it did not disengage and was leaking quite fast.
Pumped up the driver side and it did disengage and did not leak. So now it's safe to say I need an IWE. Thanks again.

 

Yes, if the IWE actuator at the wheel, when pumped up, leaks and does not disengage, it is a pretty much a sure bet that you need a new one.

 

You might want to look at the pictures here also.

http://www.f150online.com/forums/200...replacing.html

The pictures/discussion after using XJC89's trouble shooting guide, helped me save almost $1000 in labor replacing both my front IWEs. None of the 4x4 repairs are very difficult once you understand how it all works.