Tomorrow I plan to change the bad IWE on my truck and document with pictures and diagrams along with a list of tools needed. This has been one of the least documented repairs that I've had to do, so I plan to change all that for the next guy. (it might be you... ) I recently found on the net www.helminc.com for subscription factory service manuals and bought 72 hours use to get the pages I needed for the repair. This is a great service if you just need quick a look at the manual for reference or repair. (You get access to the full manual as well as wiring diagrams and can save as PDF's).

I happened to decide afterwards with the market like it is with used cars right now, I plan to keep this truck a long time, so I found a set of factory Ford F150 service manuals on ebay for $59! (cheap compared to $30 for a crappy Haynes manual and the like) and a factory Ford wiring diagram book for $9. If anyone is interested, this is the link to the F150 section of Helm.http://www.helminc.com/helm/search_s...RKB2BBWBU23CJ0

Once I get done and get my pictures and diagrams together, I'll post a site for all eternity.

Stay tuned.

**UPDATE**

I now have the files up for download here:


Driveline System Diagnosis
IWE Replacement Instructions
System Description and Operation
Diagnosis and Testing
**NEW 6/8/2011**

**UPDATE**

edit: Never say forever or "a long time"...the truck is gone.

 

That would be great! I am interested in seeing the process, because mine make some noise when engaging, when the temp is 25 or below, leading me to believe there is some moisture in mine. What are yours doing that requires them to be replaced? I look forward to your how-to on this, and thanks in advance!

 

It started out a faint whine as it got colder to the point of when I needed 4WD it would not engage. Now if it's below freezing, I have to drive in 4HI even though the front wheels are not engaged to stop the noise and further damage. I changed the vacuum solenoid per the TSB but that pretty much did nothing different. I took it in to my local dealer and they said it was the RF IWE. Actually they said HUB but so far I have seen no one with the same issue that needed a whole hub. I think the dealer was trying to make some extra cash in a slow economy.

 

I just had the solenoid replaced on mine and the dealer said the problem was fixed. I left the dealer and within two blocks could tell the problem was still there. They tell me the next step is to replace the hub actuators. I have the feeling that isn't going to be cheap.

 

My dealer quoted $592 for one... yeah right...

I bought the parts from Tasca Ford for $73 plus $9 shipping and a few hours of my time.

 

OK...Well I decided to just post the pics here with the write up since I didn't get a WHOLE lot of pics but there wasn't much to take pictures of. We all know how to remove the wheels and the rest is just a matter of removing the outer CV center nut, tie-rod nut and the upper ball-joint nut and separating both. After this there is 3 small bolts holding the actuator on the hub that get removed. Then we see inside the actuator and what I was not finding here or on the net to get my head around how this system worked. I kinda had an idea but seeing is priceless.

So once the shaft is out of the hub, the actuator comes right off it. The CV has a gear the contacts the actuator all the time and when switched to 4WD it is released into the hub where it grabs the hub gear.


You can see after I cleaned all the old grease and particles of actuator gear off that the hub gear DOES take some damage from this issue. The actuator gear is made much softer so it takes the majority of damage. I'm assuming the gear was already slightly beveled so the actuator gear can click right on but it did have some burrs along the gear teeth.


Next we see the difference new to old and what happens to it when you hear the noise. The new gear has a flat edge to the hub side of the gear and you can clearly see that on the old one this has been ground to about a 30 degree angle shorting the gear to the point of nothing more to engage, so with the open diff taking the path of least resistance that half shaft will spin when in 4WD and the other, even though it works, will not do anything. No 4WD...



Bottom line, if you hear the noise immediately try to switch to 4HI and try to make it engage, get it in to be fixed before the actuator or hub gear are damaged or do like I did and take 2 hours and about $130 ($43 for vacuum sol. (the cause of the malfunction) and $83 for act. (the victim) ) worth of parts and fix it yourself. That time includes rotating my tires, testing the 4WD system to see which actuator was bad and changing it. I could do one now by itself in probably less than 45 minutes. If anyone would like, I have the PDF's of the manual for several pages regarding the front diff. including the pages for the replacement procedure for the IWE's. Email me and I will send them.

**UPDATE**

I now have the files up for download here:


Driveline System Diagnosis
IWE Replacement Instructions
System Description and Operation
TSB 06-08-15

**UPDATE**


**NEW 6/8/2011**
Diagnosis and Testing
**NEW 6/8/2011**

**UPDATE**

 

Thanks for the pics. I am still not 100% on how these work...like those outside teeth on the dangling shaft? Where do those engage? I guess I am not understanding where the worn piece fits into the process. Glad to hear you got yours back working!

 

I forgot!

Tools used:

once you remove the wheel...
13mm socket for outer axle nut
21mm wrench and socket for tie-rod and ball joint
24oz hammer to separate the above
(I also used a 10mm and 3/8" wrench on the above end of threads hex to hold them from spinning)
5/16" wrench or socket for the IWE bolts
elbow grease

**UPDATE**

I now have the files up for download here:

Driveline System Diagnosis
IWE Replacement Instructions
System Description and Operation
TSB 06-08-15

**UPDATE**

 

I'll mark up the pictures and post pics of the Ford manual instructions.

Basically the the dangling shaft is the outer CV joint and the IWE stays on this gear at all times. The IWE has a small bladder around the outside that when vacuum is applied it sucks the gear AWAY from the outer hub gear and you are in 2WD. When the vacuum is cut off through turning the switch, the bladder releases and all gears mesh and you have 4WD.

Give me a little bit to mark up upload some pics...

 

Good job. If mine decide to take a dump I know to call to come over and fix them

 

Nice write up and pics. It is good to hear that this a somewhat easy job if you are mechanically inclined. Hopefully mine will keep working for a long time, but if they don't I will take your route and try it myself.

 

Great write-up TN-F-150,

I'm going to bookmark this one. Nice to see the pics, I wasn't sure exactly how this worked.

Do you think that the wear on the hub and actuator gears could be decreased, or their life extended, by only switching into 4wd at a standstill rather than on the fly?

 

Heehee!

 

It REALLY is an easy fix. I would give it a 2 out of 5 on a difficulty level. I have worked on cars all my life and professionally for 12 years up to 1995 and this is one of the fixes that we would have called (and I'm sure the dealer charging $500+ to do it also does) a gravy job.

 

Funny you mention that. I was thinking the same thing during this repair. I looked at the manual and it recommends only switching to 4HI at basically 45mph or less so I would say that, yeah, If you can stop to switch it I would. I think other brands and pre-2004 F150's who still use the old way I don't think it makes much difference. Systems on the pre-2004 F150 and Chevy for instance (not sure about the new ones) work differently.

The 2004-> use this system to reduce moving parts while in 2WD to save fuel. Nothing up front turns till you turn the switch. It engages the front axle actuators and the front shaft at the same time when switched. The older F150, Chevy and prob Dodge (never looked at Dodge) front axle systems all turn all the time by splined outer CV's that turn as the wheel turns and the switch to 4WD engages only the front shaft at the transfer case. IMO, ours has an Achilles heel that would be the vacuum solenoid. When this fails, it costs money down the line. It's pretty smart engineering but there is just more room for failure with the solenoid, vacuum lines, and the actuators.