2005 4x4 won't engage even with new solenoid.
 

So my 2005 F150 4x4 doesn't seem to want to engage. Makes for a rude awakening that it's not working when front wheels don't spin and you get stuck on a trail on the property! 4x4 light works when i shift the floor shifter. I read about problems with the solenoid on the firewall so i replaced that to no avail. There is vacuum on the one hose before i plug it into the solenoid. If i just plug the one side of the plug into the solenoid and engage the 4x4 i don't feel vacuum on the open port on the solenoid. I'm thinking if the solenoid opens correctly, i would feel vacuum. I'm not sure if that means anything. i checked fuses and didn't find any blown. Now for the other findings that may or may not be a problem. I am not very knowledgable on the inner workings of how the front differential and hubs work. I lifted the front end off the ground. The transfer case seems to work when put in and out of 4x4: The front shaft locks in and out". The right wheel hub stays locked in no matter what i do. I can't get the passenger side to lock in no matter what i do. When i spin the front drive shaft it will start to spin the short shaft going to the right wheel until it get resistance from the wheel being locked in, then i can just spin the front shaft and nothing spins on side shaft going to the wheels. That worries me but i don't fully understand how the front differential works. Thanks in advance for any insight. I know there is a ton of information out there on this subject and hopefully my problem can be narrowed down.

might have been a mistake or error, but one thread per subject please.

and welcome to the forum :wave:

Is there a relay associated with the vacuum solenoid i replaced on the firewall? I don't think it is opening when i place truck in 4x4. I may still have hub problems but i'm still not getting vacuum from one side of solenoid to the other.

I just went through all of this. I'm about 99.9% sure it's your IWE's. I had to replace both of mine, there were stuck open so they wouldn't engage my cv shafts to the wheel. And if you have 1 stuck open your just as screwed because it's an "open" diff so the one side that's not engaging is going to get all the power because it's just spinning away.

I bought a vacuum gauge today. WOW! That helped troubleshoot. My old solenoid (old design) may or may not have been bad, but I definately have bad wheel hubs. With the truck running and in 2wd, I pull the hose off one side and hook vacuum gauge up, i get nothing. The right side is shot. The left side i can still pull a little vacuum on, but it's not good either. If i plug one side (doesn't matter which) and put gauge on the other, it pulls full vacuum (~20"). Guess I'll start looking into changing out the IWE's. I know there is a wealth of info on here how to accomplish that. I'll start my personal debate with doing it myself and saving a few bucks, or forking out a few extra dollars and take it to the garage. Thanks to all who advised me. I really thought i still had a solenoid problem until i went and got the gauge. It really doesn't lie.

The IWE's are really easy to change! Don't be afraid to do it yourself

if you can do it yourself, you will save more than a few bucks. I recently had all of this done on my 2005 screw by the dealer. They replaced the IWE's, actuators on both wheels, lower ball joints while they were in thier, and it was expensive. I don't have the bill in front of my, but somewhere around 700 dollars.

I think i'm going to give it a shot this weekend and save about 200 or so dollars of labor. i jacked the front end up and really tried wobbling the tires to see if there were any loose joints on either side and didn't find any play. I don't think i'll need to change any ball joints. The upper is a little pricey. How hard do those come apart? Am i going to need a tool to pop them loose. Seems like i remember there being a "fork" that hammers in to separate them? Also, can the nuts that are removed be reused or should they be replaced?

Buckeyebrad, I am having the same problem. Did u chane ur iwes out? How easy was it? And what did u pay fir them?

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