Amen to that....my dealerships service department....worries me sometimes...they know about as much as I know...whats scary is I learn all kinds of useful info on here....then I tell them at the dealership....and when I get the vehicle back they changed everything I told them.

 

An update to the 4x4 Problems, based on info in this forum and my research on the internet.

There seems to be 2 highly frequent problems associated with the 4x4 system on the 2004-2006 F150:
1) 4WD doesn't work, interior light doesn't come on, works intermttantly, etc.
2) Front "hub" grinding sound

The typical "fix" for #1 is to replace the 4x4 solenoid at the fire wall; this goes bad on the models that don't have the "water deflector" (hood) over the solenoid. Very easy fix - basically unplug the bad one and plug in the new one.

As for #2, there appears to be a combination of "solutions", most dealing with the replacement of the IWE's &/or the "inner" hub assemblies. Before you take it to the dealer be sure to check that your vacuum lines aren't unplugged at the steering knuckle (be sure line has enough slack for lock-to-lock turns), or the vacuum line(s) doesn't have a leak.

The above are not absolute solutions as most people & the dealership don't use the proper descriptive terms for the different parts & pieces. But, this should at least get you most of the way to arriving at a reasonable diagnosis.

"Shotgun" repair by the dealership is an owners nightmare - Good Luck!

 

The sensor on the firewall was replaced with the "shrouded" one. Still didn't work. Had left hub changed as the actuator was full of water and destroyed the teeth on the hub. Still when it gets below freezing, I hear some clicking from the front axle's direction. I don't even touch the switch on the dash and it acts like it is trying to actuate anyway.

 

im reading these problems and noticed they are the same problems i had with my 99 4x4 ranger ford used the pvh hub system in them for 2 yrs before relaizing they were crap, they worked a little differently then yours, a vacuum would push a spring laoded clip together all the way to engage the hubs or halfway to disnegage them

well i would never have reliable 4x4 and i always had a humming noise after using the 4x4, but it would go away if i went back into 4x4 anyway after a while i got a grinding noise so i decided to get aftermarket manual hubs and have been problem free since, also many ranger guys have just permenatly locked the front axle, and all new 4x4 rangers have a live front axle

im not sure if there is an aftermarket manual hub for the f150 or if you can run a live axle although i see no reason why not, itll just hurt mpg but that is how the rangers 4x4 prob were solved an i fig id pass along the info

 

I found this to be true with my truck, VFR_Man helped me with this issue this past winter.
However before I knew where to check I already had my truck to the dealership. They fixed the problem. A day and a half later I had the same problem, called the dealership up again and they told me to bring it in.
When they had it on the lift I went back and sure enough unplugged again, mechanic couldnt understand why, we then looked at the other side and saw that passenger side had quite a bit more slack. On full lock the cable would get unplugged because of no slack. So he pulled the cable down on the drivers side and re-attached it. Problem fixed.......

Now my two worries are
#1.. he used a zip tie to hold the cable down, so it wouldnt come unplugged. Will the zip tie eventually rub a hole in the cable???

#2... did water get in my hubs, when I asked the mechanic about If I needed to worry about the hubs and driving it with it unplugged (grinding noise). He had said No.....but thats coming from the same guy that fixed it the first time but didnt notice that there wasnt enough cable there to keep the cable from coming unplugged again..

SD

 

I just went through a lot of these issues on my 05 FX4 with shift on the fly. I work in the auto repair biz and had it fixed there because I am past warranty. First I was getting a ratcheting noise sometimes. So I got the later solenoid. Problem persisted so I pulled the hub on the noisy side and found ruined splines. Replaced the hub and IWE and went for a ride, now the other side needs same treatment, arrgh. Did the other side, now I have 4WD again for the last month of winter.

I don't think a single dose of water will hurt, having seen the system in agonizing detail. When you get it back go for a good drive in 2WD which will get the hubs warm and suck out any moisture. Also I'd recommend engaging 4WD only while going slow, gliding, in neutral and/or stopped. 50 MPH my butt. I am positive I broke mine going uphill on a snow day doing about 25. I think I didn't lift throttle enough as I engaged 4WD, and bang.
3 weeks of RWD during the worst winter in years, not my plan. I sure am glad I bought a little FWD work car with snow tires.

 

having to deal with this very problem - truck is in the shop right now. I noticed that one of the twin lines attached to the IWE (at the wheel "hub") routes up into the engine compartment, loops over, but is not commected to anything - it's just hanging there unconnected. It's the same way on both sides. Do you guys have the same thing? If your lines are connected, what/where are they connected to?

 

Definitely connected, they ultimately go up to the solenoid on the firewall just behind the battery.

 

I just tore into mine as I'm no longer under warranty. Pulled the caliper and the four bolts holding the $300.00 hub assembly and pulled it out. The carnage was evident. The rear of the assembly has teeth on it to be engagued(sp) with the slider controlled by vacuum actuator. the slider has beveled teeth to slide into non-beveled teeth on the back of the assy. My assy has ground to a bevel from not fully sliding into ring. Suspect this happens when vacuum leaks are present. When pulling the assy, I noticed a thin rubber o-ring seal that was broken in two places. This could have happened when I pulled it out as lubrication may have dried in 38000 mi. I also found a point of interest where the stub shaft meets the vacuum seal in the rear by the boot. Will post more as I dig to the bottom of this attrocity.

 

Sounds like the issue my son is having with his 04 F150 FX4. It has been going on for some time now, so I'm pretty sure the hub is toasted. Looks like we will run new vacuum lines and replace the solenoid while we're at it. I want to thank all of the people who posted information on this. You have probably saved days of work and loss of hair.

 

look through these...

http://www.f150online.com/forums/2004-2008-f-150/360269-iwes-removal-replacing.html
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https://www.ford-trucks.com/forums/836438-everything-you-wanted-to-know-about-the-iwe-system-and-then-some.html

 

Thank you very much. I appreciate you going to the trouble to post these links.

 

so i have a 2007 f150 4wd and my tuck started today doing the same exact thing so did you ever discover what youre issue was ?

 

Pipefitter,

You can verify that this is related sound by engaging your truck in 4x4 and seeing if the noise goes away. What happens is your truck applies vacuum to the actuators when the truck is in 2 wheel drive. This disconnects the axles from the front hubs. So when there is a vacuum leak in the system, and the vehicle is in 2 wheel drive, the truck cannot supply enough vacuum to keep the actuators disengaged. Then by selecting 4x4 it just shuts of vacuum and the actuators engage.

This is actually an easy system to diagnose, and alot of people make it far more complicated than it really is. First step is to buy a hand held vacuum pump. Turn your steering wheel all the way one direction. Go and look behind one of your front tires. Look for a large rubber flexible brake hose There are other lines clipped onto it. One line is your ABS wire, and the other line (it is really 2 lines molded together) is for your IWE (4x4) actuator. Follow these down to where they attach behind your wheel, and unplug them. Using your vacuum pump in the larger of the 2 ports on the IWE actuator (not the line), pull a vacuum (18 inhg should be ok) and look to see if the IWE actuator holds vacuum. If it holds, reconnect everything and move to the next wheel. If the next wheel holds vacuum, then suspect an issue with the lines, IWE solenoid, or check valves.

To test the lines, simply get a vice grip, or some sort of small clamp, and just clamp the line off at the IWE solenoid, and pull a vacuum on the line at the wheel end. Just keep doing this until you can find the source of the leak. If there is no leak, we need to look at the IWE solenoid.

Plug your vacuum pump into the port on the IWE solenoid that feeds your wheels. Then start your truck up, (in 2x4) and see if the IWE solenoid turns the vacuum on. If when you start your truck, you get no vacuum, pull the line off that goes to your intake manifold. If you get vacuum on that line, then your problem is The IWE solenoid/wiring. If you have no vacuum on the line from the intake manifold, trace it back to the manifold and look for a damaged line. To test the check valves, simply pull a vacuum with your pump on each side of the check valve. One side will not allow you to pull a vacuum, and the other will.

If you find an issue with your IWE solenoid, grab a Multimeter and hook one lead up to your battery negative(truck running). One wire on the IWE should be 12v. Then hook your meter to the battery positive, and the other wire should read 12v.

That is IWE diagnostics in a nutshell. It can appear confusing, but it is really simple. Please shoot a response back if you have any more questions, or need more clarification on anything. You will need to do a little bit of diagnosis to properly fix this, but it is all easy stuff that anyone is capable of doing.

 

My turn for the problem, I replaced the IWE Solenoid and it didn't resolve the issue, this past saturday we really dug into it, I got a Wheel Bearing Hub in advance as a buddy and I looked at it a few weeks ago and determined that's where the grinding noise was coming from. It was grinding in 2WD and 4WD.

We started at the solenoid and worked our way down, disconnecting it and checking for vaccum, we wound of blowing out all the lines and some dust / moisture came out of
them. We also removed the vacuum reserve box behind the Battery and it had some water in it. We drained it and tested the it to see if it would hold vaccum. We then checked for vaccum at each hub and it seemed to be good.

We removed the wheel bearing HUB and their was grease everywhere. After cleaning it up we noticed the inner Wheel bearing or IWE Hub Lock Actuator seemed to be damaged slightly and along with the teeth on the Wheel Bearing Hub. since it was late in the day already ( Saturday ) we couldn't get the Hub Lock Actuator ( Dealer Only part as far as I can tell ). We tested the hub engaging with the old HUB and the new HUB and it seemed liked everything was working okay till the road test.

We then tested the 4WD as the truck was off the ground and could see the actuator moving in and out as it should be til the Road test and found in as soon as we speeded up the grinding was back in 2WD, but not in 4WD.

I plan on taking it apart again later inthe week and inspecting the axle and the Hub Lock Actuator and replacing both if necessary.

I've read all the posts and this seems to be the reason why mine 4WD has issues.