This is not true, These are positive engagement hubs. once engaged, the only thing that spins in the IWE hub is the bearings, The hub ring positivlely engages the outer hub via the spring pressure in the IWE hub. You can cap these off and run normally in 2H, But you will suffer a 2-3 mpg loss because of the giant increase in rotating mass of the half-shafts, the front Diff and the front driveshaft. If you let them grind long enough, you will have to replace the wheel hub assembly and the IWE actuator. ~$210 for the the wheel hub assembly (each side) and another 80 for the IWE actuator( each side).

I actually have one bad IWE actuator, but it failed to the point that it is always engaged. The other side is OK. Verified the problem with a vaccuum pump / gauge. The Factory workshop manuals for these truck are very good. (as expected). Cool part is , according to the manual, only 9 steps to replace the IWE actuator, (after gettting the truck up on stands)

So I plugged the vaccuum line to the drivers side IWE acutuator so as to not have a vaccuum leak on the other side, It did grind for awhile, but operation was verified ok with the vaccuum gage. My problems started with a bad IWE solenoid, which I have replaced with the redesigned rain cover.

My MPG's are down 1.5 to 2, because I'm spinning the spider gears and two half shafts. I'm assumming that the opposite halfshaft is spinning backwords, instead of spinning the driveshaft.

4wd works fine, no clunks or weird noises. and it will engage at speed.

No steering problems either. in 2H, turns normally, no binding.

When I find time, I'll get the deed done, but for now, i'm confident i'm not doing anymore damage. heck, they're only free wheeling.

 

You have to get the parts guy at you stealership to find the TSB on the IWE solenoids. In the TSB is a new part number for the revised solenoid w/ shield.
It is actually cheaper to get the solenoid that way, ~$27 bucks

 

My "stealership" doesn't care. They just went out of business this week.

 

How far is the next ford dealer? or order it online.

 

6L3Z-9E441-A IWE Solenoid is the revised part.

 

I have a related problem

I can not engage or release the hubs at increased speeds. If I'm stopped or barely moving it is fine. The transfer case is operating OK, but I get the grinding noise if I'm going at any rate of speed. Going back to 2WD at speed the tranfer case goes into 2WD, but it feels like something it is still engaged. I was going to compare the tire diameters, any other ideas?

 

Sounds like your IWE's are gummed up inside or the splines are a bit gnarled up.

 

sounds to me like your IWE vent line is plugged. this is the second smaller line attached to the IWE actuators. The vent allows the IWE to expand rapidly to engage quickly. My suggestion, pull the vacuum line and blow out the vent lines with a little commpressed air. there is nothing on the other end to create pressure, so no blowouts
also, sit in you driveway and excercise the whole 4x4 system sitting still. 4h to 2h. back and forth for a couple minutes.

 

What year is your truck? If you have a 2004-2006, check the drivers side IWE actuator with a vacuum pump. should hold vaccum. pump to 20in of vac, and see if it holds. max loss should be 1in of vacuum a minute per ford workshop manual

If not holding any vacuum, the IWE is always engaged and you need to replace it.

 

Well, I took my truck in to the dealer again (for the third time) and this time they actually heard the grinding noise. At first they said they couldnt figure it out but sure enough they found a small hole or cut in one of my vacuum lines. Apparently it was rubbing against my frame (according to the service rep).

I have yet to pick it up so we will have to wait to see if they actually fixed the problem. They did say they test drove it after the fix and it did not make the noise.

Wish me luck...

 

Bringing this back from the dead.....

So I have a question (because I think this is happening to my 07 Screw) If I am in Park, in 2wd, should I be able to turn the half shafts and the front drive line? I had about a 100 mile commute this morning and of course this went down in the first 5 miles, Just after being pulled over by CHP (the good news is he was SUPER COOL and let me go). So I pulled over and the grinding stopped, but when I slid underneath to shake stuff and check for missing parts the half shafts and axle wouldn't spin. Truck was in Park, but also in 2wd and in the past I know my old 4wd's you could spin all of this with the truck in gear (never had a 4x4 that was an Auto before).

 

This has to have something to do with it. BUt I'm an 07 so I dont know yet if the dealer will touch it or not????

https://www.ford-trucks.com/tsb/full...hp?tsb=06-8-15

 

If the engine is running yes. If not, no.

 

Oh I didnt think of that. So with the engine running does the vacuum build up and disconnect the half shafts? Thats kinda of dumb. I almost wish some one made a hub set for this front end.

 

Think of it as exercise for the hubs. Keeps 'em limbered up.
It's also fail-safe. If the vacuum lines get destroyed, you still have 4wd.