IWE Issues?

Hi Folks,

My truck recently started making this bizarre noise under light throttle openings and left hand turns. The noise can best be described as someone rattling a tambourine under the car! More recently this noise seems to have changed slightly akin to dragging a metal strap along the ground. Curiously the pitch of the noise remains the same regardless of speed or throttle opening (i.e. I can be doing 30 or 70mph in any gear and the noise is identical)

When I shift into the 4WD, the noise disappears.

Now, I was initially convinced the IWEs were not at fault because the front wheels free-wheel when the engine is running and then lock into the half-shafts with the engine off, as they should. Ergo, the IWE system is working.

Nevertheless, I cannot ignore that the noise cannot be reproduced with the transmission in 4WD and therefore, I decided to do a little test...

Having searched the internet for Raptor specific IWE problems, the issue doesn't seem as widespread as it is for the standard F150 and I was dismayed to learn that all the youtube vids/diagrams for checking the Vacuum Solenoid etc don't apply to the Raptor because its Vacuum Solenoid is on the other side of the engine bay

Anyway, What I have done therefore, is disconnect the vacuum line from the Solenoid and **** it off so that the IWEs will lock due to no vacuum.

Despite warnings that I'd lunch my tranny the second I slipped into Drive, the truck drives as normal, both in 2WD and 4WD and... I haven't heard the tambourine man come back yet

Two questions then:

1) why shouldn't I just leave it like this? I'm not bothered about 'drag' issues given that MPG is horrendous anyway and the 2.7t weight is unlikely have any noticeable impact on a couple of halfshafts being turned.
2) Am I doing any damage to the transmission? As I understand the transfer case operates off a viscous clutch which is what allows you to swap into 2/4WD on the fly. Hence in 2WD the transfer case is completely 'open'.

So unless my aspiring percussionist comes back, it looks like my answer does indeed lie with faulty IWEs (I also get the occasional pop/bang in 4WD when taking up load).

I'll run the truck like this for a while and see how I get on. I will get the issued looked at next week, but I've got a date with some sand dunes and a KTM 450 tomorrow, so I need the Raptor to work for a change...

2011 6.2l SCAB with 54k miles, by the way.

Cheers.

Good luck at the dunes. I suspect you will get stuck.

The vacuum selonoid is easy to replace and the IWEs will probably take you a few hours to do both the first time around.

However, you are still within the 60k mile power train warranty and all this should be covered by the Ford.

To answer your questions
1 - if you leave of like this the IWE will wear faster abs may not be as effective the next time you need it.

2 - the shouldn't be any damage to the transmission since the transfer case is open.

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@Yukon Joe
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Thanks for the quick reply, Joe.

Alas, my Raptor is a US import here in the UAE, so a trip to my friendly local Ford Shop back in the US is out of the question. And the local Ford agent wont touch my car with a barge pole (actually they will, but I'm pretty sure that's all they actually did to it!).

Looks like its best to swap the solenoid and the IWEs at the same time then.

Cheers

Make sure you check the vacuum lines as well, that they are not leaking. I've heard that a few times about your Ford dealers in the uae! Good luck

I would change the components. Driving in 4wd all the time is meant for loose terrain where your wheels will slip. Driving straight would be fine but not corners consistently on pavement. Eventually you will do more harm than good unless you drive it 99% off-road.

Pennyroyal Tea said:

Thanks for the quick reply, Joe.

Alas, my Raptor is a US import here in the UAE, so a trip to my friendly local Ford Shop back in the US is out of the question. And the local Ford agent wont touch my car with a barge pole (actually they will, but I'm pretty sure that's all they actually did to it!).

Looks like its best to swap the solenoid and the IWEs at the same time then.

Cheers

Click to expand...

Yes, I would.
You can order the Dorman IWEs from Amazon.

Dorman 600-105 4WD Locking Hub Actuator https://www.amazon.com/dp/B0042ORWNI/?tag=fordraptorforum-20

Not sure on the part number for the vacuum selonoid.

I also think there is a write up on here on how to change the IWE that would be helpful.

RDFTS said:

I would change the components. Driving in 4wd all the time is meant for loose terrain where your wheels will slip. Driving straight would be fine but not corners consistently on pavement. Eventually you will do more harm than good unless you drive it 99% off-road.

Click to expand...

What harm am I doing though? The front wheels are now effectively turning an open differential (<2012 car) with no drive going to it. So, apart from the negligible wear on the crown wheel etc, what am I missing?

Besides, the roads are all straight highway out here anyway, so it's not like I'm tackling the Col de Turini on my morning commute.

It's more of a theoretical question; I will be replacing the IWEs soon. But what is the point of the vacuum operated free-wheel setup? I've noticed no noticeable loss in performance, nor any measurable increase in fuel economy.

One thing I have noticed is that with the front axles now engaged, the previous vibration at highway speeds, which I had put down to my tyres being old and out of round, has now all but disappeared.

So at the moment, the car feels better the half-shafts locked in place than it ever did with the system working correctly.

Had the exact same symptoms going on which got worse. Dealership found metal shreds inside the transfer case and replaced the transfer case under warranty.

Well it's not the transfer case...

if it were, the symptoms would wither be reversed (i.e. noise appears in 4WD only) or when the hubs are locked to the front half-shafts. In 2WD, the transfer case does nothing (i.e. the clutch to the 4WD is open).

I've isolated the problem by unplugging the vacuum line to the IWEs (therefore locking the hubs) and the noise disappears completely. If I plug the vacuum line back in the noise comes back straight away.

Crucially, I'm now also getting the noise on left turns, either on or off the throttle, which tells me the nearside front IWE is the most likely culprit.

Anyway, I was on the dunes at the weekend (my weekend is Thursday and Friday ) and despite scraping and scouring the whole way there, my truck performed faultlessly in the sand, even on some pretty worn tyres. No clonks, no pops. Nothing.

Thanks for all your suggestions, folks.