So, ive been battling this problem for awhile now, and have just read through this thread, which was IMMENSLY helpful btw. But I do have a few questions if there's anyone around to answer them ? (I'm somewhat a noob. Lol) so, I encountered this problem about 2 months ago. At the time, I was insanely busy with the fire academy etc, so I just decided to sacrifice my truck for my schooling, since I didn't have any other means of transportation. When I finally finished the academy, I finally got around to taking a look, and to my dismay- I found that the vacuum line connected to the left side (looking from the front of the truck) was simply unhooked. I was too much of an idiot to even look, and couldve probably resolved it before it got bad. Anyways, when I hooked it up, the grinding (which occurs ONLY when im accelerating btw, and only after getting above around 10mph, but even at 70mph, if i let off the gas, it immeditially stops) didn't go away (coming from driver side IWE) so my guess is : bad actuator, moisture in the unhooked vacuum hose boogered up the solenoid, or I have a vacuum leak somewhere else. Now, on the passenger side, the vacuum line going from the solenoid-down is wrapped in wire loom, and at the top of the wire loom, is another vacuum-looking hose that isn't hooked up to anything (no connector or anything on the end). Is this the IWE vent line ? I know I asked several questions, none of which are very clear I imagine, but basically my question is: are my 3 conclusions about what might be wrong here accurate ? And does anyone have any idea which is the most likely ? Finally, a few users on here suggested either bypassing the solenoid, or unhooking the vacuum line from both IWEs in order to lock the hubs, but keep the transfer case out of 4wd to keep from causing any more damage, and that this will only cause a slight drop in MPG. Is this a good idea as a temporary fix ? I'm leaving to go to Mississippi on sunday (about a 6 hr trip) until I get back next week and can actually figure out the problem and fix it. I won't need my 4wd on my trip as far as I can figure, so I'm not worried about that. I just don't wanna hear the grinding or cause even more damage while I'm gone. Thank you SO much to anyone who replies. You will have my undying gratitude. And If you happen to live in tiny little Parker, fl. (haha) I promise to put your house out If it ever catches fire lol.

UPDATE: I started toying around today trying to figure out exactly what the problem was, and I located a hole in one of the vacuum lines going to (or from. Idk) the solenoid. I just cut it on both sides of the hole, stuck a vacuum hose connector in there, and taped over it with a little hose repair tape, and voila ! Drove all over town in amazement that the noise was gone ! Then I took apart the iwe on the drivers side (problem side) and there was very minor amounts of metal shavings in the grease. So I cleaned it all out, repacked it with grease, and it feels like I've got a new truck ! Lol.

 

Well I have read this thread and several others pertaining to 4x4 issues on the 04-08s and I still have a question.. Hopefully you guys can help.

Couple nights ago I was driving down the highway and all of the sudden I got the grinding noise (sounded like a piece of wire or metal dragging under the truck.) I immediately pulled over and came to a stop, and while I was coming to a stop I felt a clunk, so I'm guessing the 4wd went ahead and engaged.

When I got where I was going I decided to test and see if the 4wd was the culprit (hadn't read any of these threads yet, just went on a hunch) and when I switched it over to 4HI, the light on the dash would come on and off and keep blinking irregularly. So I switched back to 2wd, but 4x4 didn't disengage. Finally after a few more tries I got it to unlock, but when I tested to see if the 4x4 would work today I got the same blinking light issue. I'm not sure if it engaged properly or not (don't think it did) but it did disengage fine unlike the last time.

From what I've read, it sounds like I probably have a bad solenoid. But what doesn't make sense is that I got the IWE grinding noise (for the first time ever) randomly while driving down the highway, which points to a vacuum issue. But, I haven't heard the grinding again since that night.

Any ideas? Think I have a bad solenoid and maybe the 4x4 switch motor isn't working properly.. but do you guys think I need to look into the vacuum system and IWEs too?

 

When my solenoid went out it was intermittent as well. I would start there.

 

I can't seem to find any posts on my particular problem. Most of the posts in the thread regard unwanted 4x4 engagement while mine is the opposite.

The vehicle is a 2006 F-150 FX4 with 111,000 miles.

I've replaced both front hubs and actuators. I've also subbed in a new cv joint on either side. The truck has the updated solenoid on the firewall. One of the check valves was faulty (replaced it) and the other seems good (can only blow through it one way).

The truck engages in 4x4 high and the light comes on. Under heavier load in loose gravel or snow, the front wheel(s) pop/clunk out of 4x4 and re-engage when I let off the throttle. It seems to be the left front disengaging as I hear a pop/clunk and the truck pulls to the ditch on the right. The light on the dash remains on.

I'm planning on checking for vacuum leaks in the hoses and box under the battery tonight. Any other thoughts or suggestions?

 

How much do you want for the IWe? Mine just went out. Also my actuator has a gasket on it that is broken.

 

Hi all,
I have had the pleasure of owning a 2005 F150, and also had the pleasure of working of the strangest things on it. My IWE went out, changed the solenoid, and it still sounded bad. Took the wheel off and the hub. Bearings all over the place. I cleaned out the actuator and noticed that there is a hard seal inside the actuator. It is missing a piece. Anyone know if I can just buy the seal? I cant seem to find it anywhere. I dont want to pay another 100 dollars for an actuator for just a seal. I also documented and took pics of the dis-assembly. I will put them on a photo sharing site, and upload. I took a lot of up close pics. Right now however my truck is on jack stands because no one has a IWE, or actuator.

 

Ok, so I have an update. The 4wd actuator was not messed up. The seals were ok. On the wheel side of the actuator there is a plastic guide that goes only half way around. When it is greasy it looks as if the plastic guide is broken. I will post pics of the replacement when I can upload to a link. Thanks everyone for this thread. I saved a ton of money by reading this thread, and forum in general, and I hope that I can be a productive member of the forum.

 

Update on my situation- replaced solenoid and everything is good so far.

Rusty06: sounds like a vacuum leak. Disengaging when under a load/ heavy throttle and re-engaging when backing off the throttle definitely sounds like its just not holding vacuum like it should. Good luck, let us know what you figure out.

 

Update to post 154

Unfortunately, my issue has not been resolved. I replaced the solenoid last night and still no dice. I will check for damaged/cracked lines again. I think I will also replace the other check valve because they are cheap and will rule that out. The only things that have not been replaced at this point are the lines and the vacuum box.

MOford21: Glad you got your problem resolved. However, your statement does not quite make sense to me. With no vacuum, the system wants to be engaged in 4wd. It's almost as if I am getting vacuum when I don't want it, causing the system to revert to 2wd. That's what makes me think I'll replace the other check valve, just in case. Any other thoughts or suggestions would be appreciated.

Anyone think this could be a transfer case issue?

 

Well, I replaced the other check valve and purchased a vacuum gauge. The vacuum is operating properly throughout the system. I still have the same disengagement issue. I am going to check the actuators one more time before I consider taking it somewhere.

Has anyone had their transfer case go bad? The used ones are reasonably priced on ebay.

I did read somewhere that an alternator was causing voltage issues in the system causing intermittent problems in the 4wd system. So I suppose I could check that. Frustrating...

Any ideas or suggestions are welcome.

 

Well I have replaced actuators on both sides and also. Had a vacuum. Line melt causing problems there ( always locked in ). Now myquestion. To. You would be when u engage the 4x4 switch do you get you light on the. Dash read 4x4 or 4x4 low? If not your problem might be in the transfer case motor. There is a little electric motor the bolts to the transfer case with 3 bolts that has a few wires going into it. That went out on mine. The Magnet cracked off the housing and was binding with the coil. I payed 100 bucks at my local auto parts store in 30 mins. Had it on. The only thing that gave me trouble was u have to transfer 2 wires (I think) from the old plug to. The new. There were instructions how to do it and after finding them in thebox. It was easy. Hope this helps. I know I have had my fair share of problems with my 2005 f150's 4x4 but I have did all the work myself and only cost me about 300 bucks.

 

Somethingsorry I didn't read far enough of it is it the thread to see that you were getting the light to turn on on the dash. from what you were saying it sounds like you might have some actuator problems. the 4 x 4 system uses the vacuum to disengage the hubs when the truck is off or turn into 4x4 it will turn the vacuum off and the springs the iwe will push the actuators gear into the hub gear. so if you would like to eliminate your vacuum system unplug the vacuum lines on each actuator this should cause both hubs to locK. if you still in counter the same problem then you might have actuator spring problem. that just isn't to where they might not be engage in all the way

 

Rino-thanks for the reply.

I have replaced both actuators with brand new ford parts. I do get both the high and low 4x4 indicator lights in the dash. The disengaging happens in both low and high. I suppose the new actuator(s) could be bad, but i doubt it. I did disconnect the vacuum lines at the hub and the same issue still occurs. I also hooked the old actuators up to the vacuum lines and they both fully engage. I only replaced them because they had 110k miles on them and the gears looked a little worn. I replaced both front hubs at the same time.

I think i will look at the motor on the transfer case this week, as i have read the motor might not be fully engaging the transfer case where it needs to be. I will keep this updated to help others when i finally get to the root of this problem.

I did talk to my cousin as i had forgotten he had to get a new transfer case after his bit the dust at the sand dunes. He drove my truck and said his felt the same way when his went out, only worse. His truck is a nbs 2004, so same system.

 

Yeah from what you say it for sure sounds like its something in your case! Not much else it can be. Well good luck on this!

 

I have been having an issue with my IWE, actuators, etc for a while now. My truck was in 3 times while under warranty, but they could never duplicate the problem so it was never fixed. Everything was vaccum tested and passed and the solenoid was engaging when they checked it. I assumed afterwards that it may have been due to cold weather and moisture in the lines.

However, just yesterday, 59 degrees out, I had the same problem. The grinding came back and went away when engaging 4x4. Since now I don't think that it would be moisture freezing up the solenoid, what do you guys think is the actual issue?

Truck is now out of warranty which sucks too.