I am getting the IWE ratcheting sound on my 2005 F150. I'm getting vacuum at both hubs but neither actuator is disengaging. I don't know if I'm not getting enough vacuum or my actuators are actually bad. Here's the question... can I just disconnect the vacuum lines leaving the hubs engaged but still keeping the diff out of 4WD? I need a couple days to get the time to properly diagnose and get parts. If I drive like this will I screw up anything?

 

Well, after more testing I've determined that the front end seems to work okay with the hubs locked but the diff still not actuated. What I can't believe is I'm pretty sure both IWE actuators have failed within a few days of each other. the passenger side one was making noise about 3 days ago. I worked with the system today and after fiddling around I can't get either to release the half shaft properly (which seems to point to the solenoid). But, isolating the solenoid by bypassing it and the hubs still won't release the half shafts. Actually the drivers side now makes noise in 2WD(even with the hoses unplugged from the actuators themselves). I had to blow air back into the drivers side to lock the splines in. I've got the vacuum line fro the motor side plugged into the solenoid and the other port on the solenoid capped off. Switch is in 2WD. I should be able to run like this for a few days without issue til I get a pair of actuators, correct?

 

I'm no expert, so take this FWIW.

I thought when the front hubs were locked it was like a solid axle. The front "differential" isn't really a "differential" but just a system for locking the front axle to the drive line, right? This would mean that you are OK as long as you don't steer too much (which would cause one tire to scrub).

Perhaps others who know the system better can chime in.

As far as the problem is concerned, the sticky thread at the top of the forum discusses how different levels of vacuum cause different actions of the hubs.

Good luck getting it solved - it seems improbable that both hubs would crap out so close to each other.

 

The actuators need vacuum to disengage from the hub. If you don't have vacuum at the actuator then they will be engaged. There is so much great information on here about this issue.
Good luck! I'm still working on my issue as well

 

You are fine to drive with the vacuum disengaged, and IWEs engaged.

The IWEs can fail internally. They have a seal that can fail, internal springs that can fail, as well as the gear teeth themselves.

The good news is, parts are not terribly expensive (online sources), and the repairs are relatively easy to do.

Lots of us have "been there" and are even sprinkled through these threads. Read on...

http://www.f150forum.com/f72/how-dia...m-esof-186872/

https://www.ford-trucks.com/forums/8...then-some.html

http://www.f150online.com/forums/2004-2008-f-150/360269-iwes-removal-replacing.html